Eawag Annual Report 2008

Home , Lake retention time, Orpund

[email protected] www.eawag.ch 28 50 823 (0)44 +41 Fax 11 55 823 Tel. (0)44 +41 Switzerland Dübendorf 8600 Überlandstrasse 133 Eawag

Eawag Annual Report 2008 Annual Report Eawag: Swiss Federal Institute of Aquatic Science and Technology and Science Aquatic of Institute Federal Swiss Eawag: 2008 Eawag, the Swiss Federal Institute of Aquatic Science and Technology, is part This Annual Report presents only a small selection of Eawag’s of the ETH Domain. This comprises the Swiss Federal Institutes of Technology research, teaching and consulting activities. It is also available in Zurich (ETHZ) and Lausanne (EPFL), Eawag and three other independent, in German. A database listing all publications by Eawag application- oriented research institutes – the Paul Scherrer Institute (PSI), the staff (including article summaries) is available online at: Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) and http://library.eawag-empa.ch/eawag_publications.html the Materials Science and Technology Research Institution (Empa). Open access publications can be downloaded free of charge. Nationally rooted and internationally networked, Eawag is concerned with The database is searchable by author, title or keyword. If you concepts and technologies for the sustainable management of water have any queries, please contact: [email protected] resources and aquatic ecosystems. In cooperation with universities, other research centres, public authorities, the private sector and NGOs, Eawag The e-mail addresses of all staff are available via the search strives to harmonize ecological, economic and social interests in water, function on the website: www.eawag.ch providing a link between science and practical applications. About 400 staff are employed in research, teaching and consulting at the Dübendorf (Zurich) and Kastanienbaum (Lucerne) sites.

Publication details

Concept, editing and all unsigned texts: Andri Bryner, Eawag Pages 10 and 15: Beat Jordi, Biel Pages 14 and 28: Annette Ryser, Liebefeld Page 25: Nicole Basieux, Murten (co-author) Page 40: Martina Bauchrowitz, Eawag

All unattributed photos: Eawag Page 2: ETH Zurich, Susi Lindig Pages 18/19 and 46/47: Stefan Kubli, Zurich Page 18, Law Faculty Library: Canton Zurich Building Directorate Page 32, Leaping lake trout: Béat App, Orpund Page 33, Lake trout: Michel Roggo, Freiburg Cover: Günter Bolzern, Bülach

Graphics: Yvonne Lehnhard, Peter Nadler Design: TBS Identity, Zurich Layout: SLS Nadler, Fällanden Printing: Mattenbach AG, Winterthur Translation: Jeff Acheson, Bottmingen Copyright: Eawag, May 2009. Reproduction is permissible with citation of the source: “Eawag – aquatic research; Annual Report 2008”. Specimen copies should be sent to: Eawag, Communication, P.O. Box 611, 8600 Dübendorf, Switzerland

Cover photo Kirsten Klappert, Caroline Baumgartner and Eawag, Überlandstrasse 133, P.O. Box 611, 8600 Dübendorf, Switzerland Irene Keller – reseachers in the Aquatic Ecology Tel. +41 (0)44 823 55 11, Fax +41 (0)44 823 50 28 department – collecting samples for analysis of the “common freshwater shrimp” (Gammarus spp.). Eawag, Seestrasse 79, 6047 Kastanienbaum, Switzerland Photo: Günter Bolzern, Bülach Tel. +41 (0)41 349 21 11, Fax +41 (0)41 349 21 68 Content

2 Letter from the Director Prof. Dr. Janet Hering 4 Swiss Ecotox Centre now operational 6 Forum Chriesbach: reaping the rewards of sustainable construction

8–19 Urban water systems 11 Membrane filters for safe drinking water 14 Tackling waste problems with small-scale biogas plants 15 Wastewater for environmentally sound heating 16 Tracking the growth of cholera bacteria 17 Eawag consulting: millions of francs saved 18 Photo reportage: Copper – not a fish-friendly substance

20–33 Aquatic ecosystems 23 Species formation and disappearance influenced by humans 26 Niche differentiation – room for numerous species 28 Three-spined stickleback: successful invasion of Switzerland 29 Hydropeaking: impacts on migrating fish 30 Revealing the secrets of the lake floor 31 Modular Stepwise Procedure: Optimizing river restoration efforts 32 Photo reportage: Monitoring lake trout with transmitters

34–47 Chemicals and their impacts 37 Endocrine-disrupting chemicals 40 Nonylphenols: it all depends on the mixture 41 Silver nanoparticles: toxic to algae 42 Reduced leaching of herbicides from bitumen sheets 43 Broadening and tightening the net 44 Arsenic: risk identification and mitigation 46 Photo reportage: Removing toxic sludge from Lake Zurich

48–60 Eawag 2008 54 Ueli Bundi: a bridge-builder committed to sustainable water management 55 Equal opportunity and gender equity 55 Eco-Team: Natural laboratory on our doorstep 56 Organization Chart / Advisory Board 58 Finances 59 People 60 Activities 2 letter from the director

Meeting challenges – bridging theory and practice

Stewardship of the water environment − encompassing the quality and quantity of water resources, water supply and aquatic ecosystems − poses major challenges, both in itself and in relation to energy and food security issues. To meet these challenges, Eawag deploys its diverse expertise in natural and social sciences and engineering, with a multifaceted portfolio of activities in research, education and expert consulting.

In 2008, the world experienced a series of crises. The number, severity and diversity of these crises conveyed an important message: they are interrelated and global in scope. They cannot be resolved issue by issue or contaminants, such as arsenic and fluoride (p. 44). In nation by nation. Rather, the various aspects of security industrialized countries, Eawag researchers have contrib- − energy, food, water, public health and safety, as well as uted to a comprehensive study of endocrine disruptors in the economic and territorial dimensions − must be viewed the environment (p. 36) and are examining the environ- holistically, so that a solution to one problem does not mental fate and effects of emerging contaminants, such create or exacerbate another. as nanomaterials (p. 40). This research directly supports the activities and expertise of the new Centre for Applied Holistic view Ecotoxicology at Eawag and EPF Lausanne. In accordance with this holistic view, Eawag brings its specific capacities and expertise to address critical prob- Exchange between theory and practice lems in the domain of water, while also linking these Eawag conducts research that explores novel and excit- issues with other aspects of secu- ing science in the context of important problems facing rity. The linkage between water and society. The scientific basis for conserving biodiversity is Education Expert energy is evident in several Eawag developed through research that links the genetic diver- consulting projects, including the development of sity of fishes with adaptation to environmental pressures Course Continuing biogas generation in developing coun- (p. 22). The goal of bridging theory and practice is realized instruction education tries (p. 14), the recovery of heat from through projects such as Wave21, which actively engages Thesis Applied supervision research wastewater (p. 15) and the study of stakeholders and practitioners in the development and the ecological consequences of hydro- evaluation of drinking water treatment and distribution power operations (p. 29). technologies (p. 10). Research The impact of water quality on human and ecosystem health is the motivation for a substantial segment of Eawag’s research. In developing countries, Eawag’s research is supporting methods for the rapid detection of disease-causing microorganisms (p. 16) and for mapping the risk associated with geogenic In the domain of water science and technology, Eawag has a mandate with three major facets – research, education and expert consulting (see Figure). In the first of these three areas, Eawag pursues high-impact research, i. e. basic research leading to fundamental advances in theory, and applied research introducing radical innovations in practice and addressing the critical needs of society. In its educational activities, Today water issues Eawag supports the Federal Institutes can no longer of Technology, Cantonal Universities and be resolved in Universities of Applied Sciences in formal course instruction and the supervision of isolation or on a student research. In its expert consulting national basis. activities, Eawag provides support and guidance for stakeholders, practitioners, industry and government through projects that address practical problems and implement solutions, as well as through continuing education for practitioners and service on expert committees and advisory boards.

A balance of activities Maintaining an appropriate balance among these activities is a constant challenge, calling for responsiveness to evolving external demands and opportunities. This balance will certainly not be the same for all individual researchers, or even for all of Eawag’s research departments, but overall it must involve a strong portfolio of activities across Eawag as a whole. Although this complex mandate imposes certain dynamic tensions, it also offers unique opportunities to bring fundamental advances in research into practice.

Strong motivation The water environment is subject to increasing pressures as a result of population growth, rising demands for food, water and energy, and climate change. The broad expertise of Eawag’s researchers in the natural and social sciences and engineering, together with their experience and activities in research, education and expert consulting, provides a unique perspective and capacity to address the complexities of stewardship of the water environment. Bringing our expertise to bear on such vital issues is a strong motivation for all of us at Eawag.

Prof. Dr Janet Hering, Director 4 opening ecotox centre

Swiss Ecotox Centre now operational

The new, federally mandated Ecotox Centre develops methods for identifying and assessing the risks of chemicals, so as to minimize adverse effects on the environment. It provides an interface between research and the application of ecotoxicological assessment methods in practice. Switzerland had previously lacked an independent institution of this kind. The Centre’s other main responsibilities include consultancy, education and networking in the ecotoxicology field. As part of the ETH Domain, the Centre is supported by Eawag and the EPF Lausanne.

With a well-attended inaugural event including a sym- posium on nanoparticles in the environment, the Swiss Centre for Applied Ecotoxicology was officially opened on ing, for example, OECD guidelines for toxicity assays or 30 October 2008. The occasion offered a forum for com- environmental standards for the assessment of chemicals munication and discussion among representatives of in- under the EU Water Framework Directive. As it is repre- dustry and research, as well as policymakers and officials. sented on the SETAC Europe Council, the Ecotox Centre Speaking at the event, National Councillor Maya Graf maintains close contacts with the globally active Society emphasized that the Ecotox Centre fills a gap: it should of Environmental Toxicology and Chemistry. become the prime source for independent expertise, applied ecotoxicological research and professional educa- Applied research tion on ecotoxicology in Switzerland. Graf had introduced A variety of applied research projects are already under a motion on toxicology research in Switzerland in 2002, way. Three examples are given below: which was one of the factors leading the Federal Council Multisens: In this project, the Ecotox Centre is develop- and Parliament to request the ETH Domain to establish a ing sensors for a whole series of chemical/physical and centre of this kind in 2007. biological tests. The aim is to permit integrated evaluation of water quality in surface waters or wastewater, on lev- Dialogue and expertise els ranging from the molecule to the ecosystem. The key Within Switzerland, the Centre acts as a hub, supporting organism for this modular testing platform is not, as has dialogue on developments in ecotoxicology and cooperat- usually been the case to date, an algal species, but the ing closely with universities and government agencies. “common freshwater shrimp” (Gammarus spp.). In the The establishment of an expert database should enable “GamTox” module, the toxicity of pollutants and pollut- it to elaborate broad-based recommendations for action on environmental issues. Ecotox Centre staff serve on national and international expert committees, develop-

Facade panels with paint containing silver nanoparticles are exposed to rainfall. The rainwater runoff is captured for ecotoxicological assessment, which involves the use of freshwater amphipods (Gammarus). In particular, effects on swimming activity and respiration are monitored. opening ecotox centre 5

Two sites: Dübendorf and Lausanne The headquarters of the Ecotox Centre – mainly concerned with aquatic ecotoxicology – is at Eawag in Dübendorf. The second site – focusing on ant mixtures is analysed for the amphipods themselves, terrestrial ecotoxicology – is at the EPF in Lausanne. The management team their food sources and their predators (e. g. fish). Thus, consists of the Centre Head (Dr Almut Gerhardt) and one delegate each from for the first time, different stages of the food chain can the Eawag Directorate and the EPFL Presidency (Professors Rik Eggen and be assessed ecotoxicologically at the same time – food Christof Holliger). As well as receiving federal funding of CHF 2 million per quality and food choice of the freshwater amphipod are year, the centre can undertake contract research, although it is not to com- influenced by pollutants that affect the microbial coloniza- pete with the private sector. Operating alongside the Ecotox Centre from tion of leaf litter. Although Multisens is rounded off by a 2009 will be the Swiss Centre of Applied Human Toxicology, hosted by the variety of laboratory tests, most of the modules can also Universities of Basel and Geneva. be used for field-testing (e. g. in surface waters). For soil ecosystems, the testing module can also be applied with woodlice. Nanosilver: Biocides with antimicrobial effects are often added to facade paints. Recently, silver nanoparticles have also been used for this purpose. It has already been shown by the Urban Water Management department National Councillor at Eawag that significant amounts of substances are Maya Graf in conver- sation with Christof washed out of facades by rainwater and may enter sur- Holliger (EPFL), face waters. In cooperation with Empa and Eawag, the Almut Gerhardt Ecotox Centre is currently using facade panels exposed (Centre Head) and to artificial rainfall to study the acute toxicity of runoff on Rik Eggen (Eawag) aquatic organisms (see also p. 40). at the opening of the Ecotox Centre. Earthworms as test organisms: At the Lausanne site, the Centre is developing soil ecotoxicology tests, focusing on the use of earthworms and springtails as test organisms. Particular attention is being paid to the optimization of existing OECD assays and to the development of straightforward rapid tests suitable for in situ use. ings and summarizes them for practitioners. It has already produced independent overviews of biological detection Professional education methods for endocrine disruptors in the environment, and Today, information on ecotoxicology is scattered over a of the relevance of the freshwater amphipod in ecotoxi- wide range of sources and often contained in highly spe- cology. An overview of the significance of terrestrial iso- cialized publications. The Centre assesses the latest find- pods (woodlice) in ecotoxicology is in preparation. These articles provide a starting point for the development of biotest systems. In the “Aktuelle Stunde” seminar series, presentations on current topics are given by internationally renowned experts from a wide variety of research institutions. In November 2008, the Centre’s coetox (“collaboration en écotoxicologie”) basic course – sponsored by Eawag, the EPFL and the Cemagref institute in Lyon – provided an overview of terrestrial and aquatic biotests. Two work- shops planned for 2009 will deal with the use of biological test methods for the detection of endocrine disruptors, and ecotoxicological methods for the assessment of pollutant mixtures. i i i

E www.oekotoxzentrum.ch Freshwater amphipods feed mainly on plant detritus in surface Contact: Dr Almut Gerhardt, [email protected] waters. 6 forum chriesbach

Forum Chriesbach: reaping the rewards of sustainable construction Eawag’s new six-storey headquarters, accommodating 220 people, has performed well since it was first occupied in 2006. A review by architects, planners and clients concluded that the results for the first two years, in terms of energy use and costs, have been positive. The internationally renowned building requires only around 64 MWh of externally supplied heating energy per year – equivalent to 6400 litres of oil. Forum Chriesbach is already regarded as a model for a new generation of buildings.

In its first two years of operation, Eawag’s new building at the Dübendorf site – with working areas containing no active heating or cooling systems – has been shown to function as intended. The values envisaged by the planners accord well with the data on temperature and energy means that little cooling energy is required for the server use. Any deviations that have occurred are attributable to room and no air-conditioning is required for the offices. changes in general operating conditions. What has proved Even during the hottest summer weeks, the indoor particularly valuable is the interaction between design and temperatures did not exceed 26 °C, which was greatly technology, cooperation on the part of the clients, and appreciated by staff. The pleasant working climate was

the reliance on simple principles. These include excellent also confirmed by measurements of CO2 concentrations 3 thermal insulation, energy-efficient equipment, comfort in indoor air: with a mean value of 0.6 litres of CO2 per m ventilation and an effective control system. air, these were very low. External heating requirements were higher than pre- Natural cooling in the summer dicted. In 2007, rather than 24 MWh, 64 MWh was sup- The building’s performance has been particularly good plied by the Empa/Eawag district heating network. This with regard to the energy required for cooling during the is still equivalent to only 6 kWh per m2 treated floor summer. Worldwide, cooling energy requirements are area (11,170 m2); expressed in different terms, energy increasing, especially for glass-fronted office buildings. Rather than using a high-tech system, Forum Chriesbach exploits the chimney effect in the atrium to cool the building overnight in the summer. This ventilation, combined with air supplied from an earth-to-air heat exchanger,

Forum Chriesbach, with the childcare centre in the foreground. Visible in the background are the laboratory building and the office block (refurbished in 2008). The servers are among the biggest electricity consumers in the building, but this makes the server room an important source of heat. forum chriesbach 7

consumption is the same as for two conventional sin- Taking stock gle-family homes – a value clearly below the stringent Eawag’s new headquarters, designed by the architectural firm Bob Gysin + Partner (BGP), “Minergie P” requirement. The higher heating require- has been in operation since June 2006. From the initial planning stage, Eawag and Empa ments are partly due to lower-than-projected occupancy aimed to make the building a model of sustainability in practice, not only environmentally, levels for the seminar and meeting rooms. This means but also in social and economic terms. The need for action in the building sector is clear: that fewer internal heat sources – employees, comput- households and workplaces account for more than half of our total energy consumption. The detailed energy statistics and the construction and operating costs for Forum ers and lighting – are available. In addition, following staff Chriesbach were the subject of an accompanying project carried out by the two research feedback, the temperature of the air supplied had to be institutes Eawag and Empa and the engineering consultancy 3-Plan Haustechnik AG. This increased slightly to 21 °C. project was also supported by the Federal Office of Energy, and the costs study prepared In 2007, electricity consumption was also higher: rather by Reuss Engineering AG (an independent consultancy) received additional support from the than the planned 121 MWh, 195 MWh was supplied ETH Board. from the grid (i. e. 17 kWh per m2 treated floor area). This was due to the staff canteen aQa – producing more than 260 rather than 150 meals per day – and the more frequent and extended use of corridor lighting. On the other Worthwhile additional investments hand, the photovoltaic system on the flat roof generated At CHF 30 million, the construction costs for Eawag’s not 60 but 71 MWh, and the thermal solar collectors sup- new headquarters were over CHF 2 million below the plied not 24 but 26 MWh per year. credit limit approved by the Federal Parliament. These costs were analysed in an additional study forming part Fine-tuning essential of the detailed energy assessment project. The additional A building on the scale of Forum Chriesbach is not sim- investments – compared with a similar, conventionally ply “finished” once the keys have been handed over. constructed building – amounted to just under 5 %. The People had to be aware that not everything is correctly somewhat higher life-cycle capital costs are however adjusted so that it works properly from the outset, and offset by the lower operating costs after only approx. that control systems have to be adapted to the individual 13 years. If energy prices rise as expected, the ben- characteristics of the building and its users. Operational efits will become even more marked. Thus, energy- and optimization is far more than just remedying defects resource-efficient construction pays off financially. In within the warranty period, and it calls for expert manage- addition, a building constructed on sustainable principles ment. For example, the automatic system used to open offers further advantages which are difficult to quantify in the tilt windows for overnight cooling comprises more economic terms, such as high value preservation, or satis- than 200 electric motors, which were – needlessly – per- faction and prestige for users and investors. manently switched on. Adjustment of the control system “saved” 20 MWh per year, which is almost a third of the Need for team spirit total power generated by the rooftop photovoltaic system. In a pioneering project of this kind, planning plays a Fine-tuning was also needed for the system controlling particularly significant role. It is essential that the client the blue glass fins that shade the facade. The spring and should not only provide clear specifications when inviting autumn settings were depriving the interior of precious architects and planners to tender, but should remain part daylight. Even after the completion of the 2-year optimiza- of the team throughout the project. Room for improve- tion period, there is still scope for further improvements. ment was identified both in the construction processes and in the assignment of responsibilities. The subordinate position of the architects vis-à-vis the general contrac- tors gave rise to some friction. The recipe for success, it was concluded, is for all parties to be not only experts in their own field, but also prepared to engage with other disciplines, convinced that significant innovations can be achieved by working together. i i i Photos: Eawag/Stefan Kubli

E www.forumchriesbach.eawag.ch E www.bfe.admin.ch/dokumentation/energieforschung/ (Energy research database) Guided tours: Ilse Hildbrand, [email protected] Contact: The auditorium is occupied less often than had been assumed – one reason Dr Herbert Güttinger, [email protected] why supplies of external heating energy were higher than predicted.

Urban water systemsWat er in

At Eawag, we develop modern strategies for water provision and wastewater management research to meet the needs of Switzerland and other industrialized countries. This includes not only Advancing towards solutions engineering solutions for drinking water supplies, sewerage and wastewater treatment plants Maryna Peter, who studied Chemical Engineering at the but also studying and preventing releases of National Technical University of Ukraine, is currently pollutants from urban areas into surface waters. working on her doctoral thesis at Eawag. As part of the We also focus on the development of sanitation EU project TECHNEAU (Technology Enabled Universal approaches specifically designed for developing Access to Safe Water), she is researching a filter module countries, which canurban be implemented in partner- in which water is purified as it passes through a mem- areas ship with the people concerned. brane at low pressure. As this system does not require elaborate maintenance or control, it is particularly suit able for use by households in developing and emerging countries (see p. 10). “For me,” says Maryna Peter, “what is attractive about research at Eawag is the process of following something all the way from the initial discovery of a phenomenon to the development of a technology, and advancing step by step towards solutions.” Does she dream of patenting a device and reaping financial rewards for her efforts? With a smile, the young woman replies: “No. If our results help more people to gain access to safe drinking water, then that’s sufficient motivation.” She adds that she is particularly interested in exploring the underlying mechanisms. As she points out, the manufacturers of a similar system operating at low pressure don’t know why it works. “Now that we’ve identified the opportunities and limitations of our filters, we can use this knowledge to set about improving them.” Teaching Welcoming argument

Willi Gujer, Professor of Urban Water Management at the ETH Zurich, has been a member of the Eawag Direc- torate since 2001. In 2006, he received the “Golden Wat erOwl” from the ETH student associationin for his outstand- ing performance as a teacher. In 2008, he also received the Tom KawaraTom “Credit Suisse Award for Best Teaching”. Willi Gujer is convinced consulting that environmental engineering is an Saving millions attractive field for young students: Bruno Storni is a computer systems engineer. With his urban areas“A large proportion company, he develops and programs electronic control of humankind does systems for industrial processes and the aerospace sec- not have access to safe drinking water – this represents tor. As a member of the Gordola local authority, he is an enormous challenge.” In his view, urban water man- responsible for the water supply system. Here, thanks to agement is a broad discipline, including “not only hydrau- the consulting services of Eawag (supported by several lics, but also hydrology, microbiology, chemistry and dissertations), it was possible to shelve a large-scale economics”. He emphasizes that the multidisciplinary expansion project approach also appeals to women. And what is the secret dating from the of his exemplary teaching? “It’s important that the lec- 1990s; as a result, turer should be highly motivated,” says Gujer, “and it’s all around CHF 10 mil- right to expect something of your students; you have to lion and a large take them seriously. They have a right to learn something amount of energy rather than just being required to sit through lectures. But have been saved you learn most,” he concludes, “with active participation. to date (see p. 17). It’s a pity there’s hardly ever much scope for argument Storni comments: with students.” “We could have engaged private consultants for certain parts of the work, as we do today with some success. But without Eawag’s expertise, the innovative approach, considering both the consumer’s and the supplier’s perspective, would not have been adopted.” The incentives for a genuinely sustainable infrastructure, he believes, remain ineffective – for example, because planning fees are based on the investment volume for the facilities concerned. Storni is convinced that more could be done. The ever-more apparent benefits for his municipality are increasingly turn- ing critics into imitators. “Eawag’s high level of credibility has contributed significantly to this process,” he adds.

urban water systems 11

Membrane filters for drinkingsafe water

In close cooperation with public water utilities and the private sector, Eawag is developing more effective methods for the treatment of drinking water. Membrane filtration is playing a key role in these efforts. The ver- satility and relatively low costs of this approach can help to ensure safe drinking water supplies – not only in Switzerland but also in developing and emerging countries.

Until the end of 2007, the Frutigen Water Supply As- sociation in the Bernese Oberland often had to divert springwater unused into the Leimbach for days at a time, especially after thunderstorms or during the thaw period. confronted with the problem of highly variable raw water Although the Fuchschrummen reservoir, built in 1968, quality. Increased turbidity levels are often associated was equipped with a chlorination system for the disinfec- with excessive microbial contamination (parasites, bacte- tion of raw water, this classical treatment method was ria and viruses). unable to deal with storm-related turbidity. The karstic springs tapped above Frutigen arise on the Effective filtration process flanks of the Niesen mountain range, where – because of Since December 2007, in spite of these unfavourable the geological conditions – precipitation infiltrates rapidly conditions, the drinking water flowing into Frutigen’s and is inadequately filtered as it passes naturally through (600 m3 capacity) reservoirs has been crystal-clear and the soil. This situation is typical of a large number of microbiologically safe. This is due to the replacement of karstic springs in the Swiss pre-Alps, in the Jura, and in the ageing chlorination facility by a membrane ultrafiltra- the mountainous cantons of Valais and Graubünden. Ac- tion system – a technology researched and refined by cordingly, water suppliers in these regions are frequently Eawag. Ultrafiltration, which is effective in all weathers, has made it possible for the association to increase the security of supplies without having to develop further raw water resources or create additional storage volume. After passing through a prefilter, which removes coarse particles, the karstic water enters a membrane filter system consisting of 40 modules, producing up to 108 m3

About a fifth of Switzerland’s drinking water is pumped from lakes. In a pilot project at the Lengg waterworks in Zurich, Eawag researchers aim to establish which treatment steps and process combinations ensure a high level of safety without unduly increasing operating costs. (Photos: Ruedi Keller, Andri Bryner) 12 urban water systems

drinking water per hour. In this process, the membrane pores – only a fraction of a micrometre in diameter – act as a physical barrier, permitting the passage of water and dissolved mineral salts, but effectively retaining turbid matter and microorganisms, including parasites and viruses. The mechanical cleaning thus also serves to disinfect the springwater, without requiring the use of ranging from 1 to 480 m3 per hour. From the outset, chemicals such as chlorine or ozone. Eawag has played a major role in the development of this technology – through basic research, support for pilot Regular cleaning projects and specific contributions to the optimization of After heavy precipitation, the turbidity of raw water in Fru- membrane filtration for drinking water treatment. tigen rises to levels comparable to those found in weakly contaminated wastewater. This gave rise to concerns Elusive pollutants that the permeability of the ultrafine membrane pores For Wouter Pronk, a process engineer and head of the might be impaired by the high particle Membrane Technology group in the Urban Water Man- Method Pore size [µm] load. In order to prevent clogging, a agement department of Eawag, ultrafiltration of spring- Microfiltration > 0 . 0 5 computer-controlled system interrupts and groundwater is a viable alternative to conventional the inflow of water to the filters up to process chains such as flocculation, sand filtration, ozona- Ultrafiltration 0.002– 0.05 three times a day so that the mem- tion, activated carbon filtration and chlorination for safety Nanofiltration 0.001– 0.002 branes can be disinfected with bleach purposes. As he points out, the process is less technically Reverse osmosis < 0 . 0 0 1 and then rinsed with fresh water. The demanding for the operators of water utilities and ensures Comparison of membrane filtration methods. fully automatic treatment plant has a – at relatively low cost – the reliable elimination of poten- A micrometre (µm) is a thousandth of a low external energy requirement, as tially hazardous microorganisms. “However,” he adds, “if millimetre. the springwater – despite previously the raw water to be treated also contains pollutants, taste passing through a hydropower turbine – still has sufficient and odour compounds or too much assimilable organic hydraulic pressure (1 bar) for ultrafiltration. carbon (AOC), ultrafiltration has to be supplemented In view of its numerous advantages, ultrafiltration is with a combination of ozonation and activated carbon increasingly being used by waterworks in this country to filtration.” replace existing processes for the treatment of springwater. In recent years, particularly in karstic regions, a Simpler treatment of lake water number of systems have been installed, with capacities To ensure that the microbiological safety requirements of Swiss food legislation are complied with at all times, 33 % of the 1000 million m3 of water processed each year by public utilities has to undergo single-stage, and another 29 % multi-stage treatment. Process chains are absolutely Suitable for use in developing countries essential at the 30 lake water treatment plants which to- Access to sufficient quantities of safe drinking water is one of the most effective instru- gether supply almost a fifth of the country’s drinking wa- ments for combating poverty. Today, however, more than a billion people are still denied ter. Here, too, ultrafiltration is increasingly being applied at this fundamental right. Especially in the poorer countries of Asia and Africa, water supply networks are non-existent or unreliable in many areas. new or renovated facilities, generally at the end of a chain Even under adverse conditions, membrane technology can make a significant contribution involving ozonation and activated carbon filtration. to the resolution of this problem. Eawag is therefore involved in the development of simple Membrane filtration requires not only a significantly filter systems for decentralized use which operate with gravity flow alone, so that there is smaller area than traditional sand filtration basins, but no need for pumps, external power supplies or purification chemicals. Surprisingly enough, also lower chemical and energy inputs than conventional the results of research carried out so far indicate that – if certain requirements are met – systems of this type can ensure safe disinfection of microbially contaminated raw water for treatment processes. Consequently, it is less costly and a period of months, even without backwashing or chemical cleaning of the membranes. If at the same time purifies raw water more effectively, as a membrane is only operated under low-pressure conditions, the biofilm that forms – after shown for example by analyses of drinking water pro- an initial drop in performance – leads to duced at the Männedorf (Canton Zurich) lake water plant stabilization of the flux through the filter. which opened at the end of 2005. Here, up to 6000 m3 If the filters are occasionally flushed with clean water, such systems can even oper- per day of raw water pretreated with ozone and activated ate effectively for years. carbon is purified in 164 membrane modules. Suspended The low-cost technology is suitable for solids and microorganisms (e. g. bacteria and viruses) are use in businesses, households and com- eliminated by filters with a pore size of 0.02 µm and a munities, as well as in emergencies or in disaster areas. For this purpose, Eawag, in partnership with Veolia (one of the world’s largest environmental services companies), has developed a pilot system for low-pressure ultrafiltration in a freight container (photo). urban water systems 13

total surface area of 7380 m2. The analytical procedures required were tested and established by Eawag scientists in cooperation with the supplier Wabag.

Optimum process combination Eawag is also collaborating closely with Zurich Water- works (WVZ) to further optimize the preparation of high- quality drinking water from surface waters. Using state- AWA, Canton. Bern+ of-the-art analytical methods, Eawag is testing various treatment technologies and process combinations at laboratory and pilot scale for the Lengg plant – the country’s largest lake water treatment facility, with a daily capacity of 250,000 m3. The aim is to apply the treatment methods that are most appropriate given the specific raw water quality. Here, the prior analyses of water quality cover Interior of a membrane (ultra)filter. The pore parameters that are not otherwise routinely investigated size is in the range – but are crucial for the product water – such as nano- 2–50 nm. The mem- particles, natural organic matter (NOM), taste and odour brane surface area compounds and assimilable organic carbon (AOC), as well per module is around 2 as cell count and pathogenic microorganisms. 50 m .

Enhancing membrane performance Some of these constituents of raw water, such as NOM and dissolved iron or manganese, can clog the mem- AWA, Canton. Bern branes and impair their performance; this is known as membrane fouling. By carrying out basic research on this problem, Eawag is promoting a better understanding of the process. For example, it has been shown, contrary to expectations, that ultrafiltration membranes are less susceptible to clogging than the coarser pores in microfiltration. It appears that, with ultrafiltration, the finest water constituents are retained by the cake layer, whereas with larger pores – of the same order of magnitude as the particles themselves – they are readily trapped, causing a blockage. On the basis of such findings, Eawag researchers are developing models to make it possible to predict the permeability – and hence purification performance – of membranes as a function of raw water quality. Wouter Pronk explains: “With these foundations, we hope to be The ultrafiltration able to optimize the design of ultrafiltration systems and system in Frutigen also to evaluate strategies for enhancing the performance (Canton Bern) comprises 40 modules of membrane filtration processes, which includes, for (cylinders containing example, operating conditions such as hydraulic pressure, the membranes). membrane cleaning and if necessary also additional processes for the pretreatment of raw water.” i i i

10 µm

st “Drinking water in the 21 century” project: 3-D laser microscopic E www.wave21.eawag.ch image: cavities form E Eawag News Nr. 65e: “From source to tap – good-quality Cells Other constituents Membrane between the mem- drinking water for today and tomorrow” brane and the biofilm. Contact: Dr Wouter Pronk, [email protected] Prof. Dr Urs von Gunten, [email protected] 14 urban water systems

Tackling waste problems with small-scale biogas plants To combat the problem of waste in cities of developing countries, Eawag researchers are studying new options for the processing of organic household waste. A particularly promising approach is the production of biogas – even on a small scale, using simple technologies.

In developing countries, ever-increas- 2 kilograms of kitchen waste per ing volumes of waste in urban areas day can yield 200 litres of biogas – pose major risks to human health and enough to cook with for 45 minutes, the environment. Soil and ground- saving firewood or other types of water are polluted by the seepage of fuel. In addition, the digestion resi- leachate from open landfills, where due serves as a nutrient-rich fertilizer organic matter often for gardens. Just because a accounts for up to system works 70 % of solid waste. Enhancing performance in India, it can’t In addition, the dumps and safety are foul-smelling and Yvonne Vögeli of the Department of automatically be attract disease-carry- Water and Sanitation in Developing To prevent blockage of the gas line, conden- transplanted to ing rats. For Eawag re- Countries (Sandec) is upbeat: “Sev- sate has to be removed continuously. Africa without any searchers addressing A proposed simple drain is shown here. eral of the pioneering projects are the issue of kitchen very promising.” However, given the modifications. and market waste, one scarcity of sound scientific data, she point is clear: ideally, organic house- this purpose are neither practical nor is studying biogas systems in India hold waste should not be dumped in economically viable for periurban and Lesotho. In a project carried out the first place. areas in developing countries. There in Tanzania in partnership with the is a need for simpler solutions – es- Ardhi University of Dar es Salaam Building on past experience pecially small-scale plants operating and the Zurich University of Applied In industrialized countries, organic at the household or community level. Sciences, she is testing a compact waste has long been treated not only But it is not necessary to start from biogas plant for household use. The by traditional composting methods scratch: Eawag has found that China, system’s functioning and perform- but also by anaerobic digestion. In India and Nepal, in particular, have ance are being analysed, and the data this process, waste is degraded by gained considerable experience on technical characteristics, environ- microorganisms in the absence of with the operation of such systems. mental acceptability and safety are oxygen, producing biogas, a mixture However, since anaerobic digestion to be used as a basis for improving of carbon dioxide and methane. How- is applied almost exclusively in rural the design, operation and mainte- ever, the high-tech systems used for areas of these countries, the input nance of a number of systems. In the material for the several million small- long term, as Vögeli point out, such scale plants is animal manure or fecal plants also need to pay off in finan- sludge. cial terms. For this reason, Eawag is seeking to gain the support of local Welcome source of energy authorities in particular. Before long, In contrast, the processing of kitchen this should enable biogas systems to and market waste is a recent devel- make a significant contribution to the opment, which has yet to become successful and sustainable manage- widespread. Pioneering projects are ment of organic household waste in mainly under way in India. The plants the developing world. i i i are of varying design and quality, ranging in size from single-household systems (1– 5 kg waste per day) to large-scale facilities (100 tonnes). Users are glad to have a simple way of disposing of their waste and also Compact biogas system for a household in Dar es Salaam (Tanzania). welcome the production of biogas, Contact: Although the plant (originally developed in India) is functional, there is Yvonne Vögeli, a lack of data, e. g. on gas yield and composition. This makes it diffi- which can be used for cooking or [email protected] cult to optimize the system and adapt it to local conditions in Africa. even for power generation. Just urban water systems 15

Wastewater for environmentally sound heating The higher-than-ambient temperature of wastewater makes it a valuable source of energy. In recent years, technologies for exploiting this potential in Switzerland have been continuously improved. Through its research and the involvement of experts from various disciplines, Eawag has contributed significantly to these advances – and to Switzerland’s leading role in this field.

In Swiss households alone, around sumption, where energy is extracted 1.2 million m3 of wastewater is pro- from wastewater with a temperature Kasag duced each day. Some of this has of around 20 °C in a temporary stor- previously been heated by boilers, age unit. Alternatively, with adequate solar collectors, washing machines and reasonably constant wastewater or dishwashers and retains its heat flows, heat recovery may also be as wastewater. If all the wastewater possible within the sewer network. in this country were to For this purpose, heat be continuously cooled With its waste- exchangers are direct- by just 1 °C, the energy water expertise, ly installed in sewer recovered would be Eawag has pipes. However, the equivalent to around heating sector pio- 300 megawatts – close provided crucial neers who installed to the output of a small support for the the first systems of nuclear power plant. heating sector this kind in the 1980s Setting aside the ques- underestimated the tion of cost-effective- pioneers. impact of biofouling in ness, our wastewater could meet the nutrient-rich raw wastewater on the heating energy requirements of more performance of heat exchangers. than 300,000 households. For exam- Within just a few days, as shown ple, when it is completed, the coun- by Eawag measurements, the devel- try’s largest wastewater energy plant opment of biofilms can reduce the – operated by the Schlieren (Canton transfer of energy by up to 40 %. Zurich) Energy Association, using However, laboratory tests also indi- Installation of a heat exchanger in a main sewer pipe. effluent from the nearby Werdhölzli cated that a temporary increase in wastewater treatment plant (WWTP) flow rates could – at least partly – – will save 5 million litres of heating flush away the unwanted layer of planners. Using simple parameters oil a year, supplying the equivalent of sewer slime. With weekly rinsing, such as temperature, discharge, 9000 “Minergie” homes. most heat exchangers almost regain distance from WWTP and sewer their original level of performance. network topography, TEMPEST can Even more heat in untreated calculate the dynamics and profile wastewater Opportunities and limits of the wastewater temperature for “In practice, however,” as Oskar revealed by modelling a planned heat recovery system Wanner of the Urban Water Man- By transferring expertise and bring- upstream of a WWTP and thus de- agement department explains, “the ing together specialists from various termine the reliable level of heat fact that many wastewater treatment areas, Eawag has helped to opti- extraction. i i i plants are located outside densely mize and promote the spread of this populated urban areas restricts the technology. It needs to be borne in use of heat recovered from WWTP mind, for example, that the recovery effluents in many places, because of heat from raw wastewater must the distance from energy users is not impair the efficiency of microbial too great. So, depending on the area treatment at WWTPs. This applies to be supplied, it may make envi- in the first instance to nitrification. ronmental sense to recover waste To ensure that the wastewater tem- heat from untreated wastewater.” perature does not fall below the criti- E www.tempest.eawag.ch This can be done locally in sizeable cal level of at least 8 °C, Eawag has Contact: housing developments or enterprises developed the interactive simulation Prof. Dr Hansruedi Siegrist, [email protected] with high levels of hot water con- program TEMPEST for engineers and 16 urban water systems

Tracking the growth of cholera bacteria

Cholera bacteria can survive and thrive not only in the human intestine but also in fresh water – and in competition with the indigenous bacteria found there. It was previously thought that, in the environment, the pathogen can only reproduce in brackish water. Using Greifensee lake water, an Eawag team obtained results that make it possible to assess the cholera risk more realistically.

To date, it has been assumed that the experiments were successfully Cholera while cholera bacteria can survive in performed with Greifensee water, Cholera is a serious bacterial infection, freshwater – where conditions are affecting the small intestine. It causes this nutrient-rich lake is not among nutrient-poor and cold compared diarrhoea and vomiting, rapidly leading them. This is because hygienic fac- with the human gut – they require to dehydration. Without treatment, the tors remain crucial in controlling slightly salty water for reproduction disease is fatal in around 50 % of cases. the spread of infection. Thanks to Cholera is mainly transmitted by contam in the environment. A team of Eawag effective wastewater treatment and inated drinking water. The disease is still researchers collected samples from prevalent in developing and emerging safe drinking water supplies, cases Lake Greifensee and countries of the South but also occurs in of cholera occur in Europe almost Good sanitation removed the bacteria Russia, China and Japan. The immediate exclusively as a result of travellers remains vital in present in the fresh- cause of the diarrhoea is a toxin secreted returning with the disease from other by the cholera bacterium in the nutrient- water by filtration. The parts of the world, such as Africa, controlling the rich small intestine. sterilized but other- South America or Southeast Asia. spread of cholera. wise unchanged lake water was then reinoculated with Newly developed method these bacteria, and cholera bacte- Competition at higher To obtain their results, the research- ria were added. In the subsequent temperatures ers used a new method developed competition for nutrients, the cholera The researchers also investigated at Eawag. In this method, rather bacteria held their own against the whether the higher temperatures ex- than culturing colonies that can be indigenous bacteria. The pathogen is pected as a result of climate change counted on nutrient plates, micro- thus able to survive and even prolifer- create a competitive advantage for organisms are directly labelled with ate not only in the intestine but also cholera bacteria. While the reproduc- antibodies and fluorescent dye and in freshwater and in competition with tion of cholera bacteria was indeed then enumerated with the aid of a the naturally occurring bacterial com- increased at higher temperatures, laser beam in a flow cytometer (a munity. the growth rate of lake water bacteria device widely used in medicine). also rose to the same extent. In the This yields more precise results in a competition for nutrients, cholera significantly shorter time than with bacteria accounted for a practically conventional methods. The method identical proportion of the total bac- is already being used, for example, by Keystone terial cell concentration at all the Zurich Waterworks (WVZ) to monitor temperatures tested. Environmental drinking water quality. In cooperation microbiologist Marius Vital says: “Al- with the private sector, Eawag is cur- though you can’t equate the artificial rently developing a version suitable laboratory situation with the much for field use, which could help to more complex natural environment, prevent epidemics when deployed in we were able to show that warmer disaster-stricken regions. i i i water does not automatically give cholera bacteria an advantage, as had previously been speculated.”

No risk from Lake Greifensee The new findings indicate that for nutrient-rich, faecally contaminated rivers and lakes – such as are often found in developing countries – the cholera risk needs to be reassessed. In general, additional potential Contact: Prof. Dr Thomas Egli, In areas where children collect water from contaminated sources – sources of infection need to be taken [email protected] as here in Harare (Zimbabwe) – the risk of cholera is particularly high. into consideration. However, while urban water systems 17

Eawag consulting: millions of francs saved

Thanks to studies carried out by Eawag, the municipality of Gordola in Canton Ticino was able to shelve the planned large-scale expansion of its water supply system, saving around CHF 10 million in investments. In addition, reductions in water consumption and the streamlining of distribution led to substantial energy savings – an example that could well be followed elsewhere.

In many communes, water supply Peak demand reduced systems are ripe for renewal, and A user survey and an analysis of avail- in many cases the infrastructure able data revealed that peak demand Bruno Storni built in the 1960s and 1970s is now in Gordola was attributable solely to oversized. Planning at that time was the sprinkling of gardens and lawns based on projected growth which and the simultaneous filling of swim- did not always materialize, and water ming pools. The water utility has consumption per capita has declined now introduced regulations whereby over the last few decades. More- private swimming pools can only be over, since 1992, “eco- filled at nighttime and nomical use of drinking Saving water according to a schedule. and process water” has means saving With this simple solu- been required under the energy, too. tion, the local authority Water Protection Act, has been able to reduce The commune of Gordola, lying at the foot of a valley on the and – in line with the polluter-pays peak demand. Further measures are Magadino Plain in Canton Ticino. Visible in the foreground is the reservoir, undergoing renovation work. principle – water users rather than currently being examined with indi- taxpayers have been responsible for vidual major users. In the near future, financing water supply systems and for example, a vegetable farm is to operations. Faced with a CHF 15 mil- be connected to the football pitch Gordola has now applied other meas- lion expansion project mothballed watering system, which is not fed ures proposed by Eawag, including since 1993 which appeared exces- with drinking water supplies. efforts to educate consumers about sively elaborate and costly, the local potential savings, the reopening authority of Gordola in Canton Ticino Producing green power of disused springs and improved sought expert advice from Eawag. The local councillor responsible for integration with neighbouring com- water supplies, Bruno Storni (see munes to allow regional optimization Scope for research and p. 9), is convinced that by saving of water supplies. These modifica- education water, energy savings can also be tions naturally required investments. The situation was analysed by the achieved. As a result of the recti- In addition, the water utility had to Urban Water Management depart- fication of leaks, which cost just invest around CHF 3 million in qual- ment of Eawag under the leadership CHF 20,000, around 120,000 kWh ity assurance and the provision of of Professor Markus Boller, with less pumping energy is now required adequate firefighting water capac- internal studies being complemented than was specified in the original ity. According to Storni, however, by a number of dissertations at the project. 2008 also saw the replace- savings of at least CHF 10 million ETH and at the Zurich University of ment of the main pipeline leading have been achieved over the original Applied Sciences School of Engi- from the springs to the distribution CHF 15 million project. i i i neering (HSZ-T). Work began with an network. The way is now clear for the assessment of the current status and implementation of another proposal a systematic search for water losses emerging from Eawag’s analysis: the from the distribution network. It soon 250 m slope down to the village is to became clear that over 500 m3 was be utilized for a small-scale power lost per day – almost a third of the plant, producing 160,000 kWh of total volume supplied – and presum- green energy per year – enough to ably this had been the case for years. meet the needs of at least 40 house- When the leaks and overflows were holds. Experience also shows that rectified, these losses were reduced greater awareness of drinking water by 80 %. In addition, a system was use, associated with water-efficient Contact Eawag: developed to permit continuous fittings and appliances, automatically Prof. Dr Willi Gujer, [email protected] monitoring of the network with the reduces hot-water consumption – Dr Max Maurer, [email protected] aid of meters installed at strategic with corresponding domestic energy Contact Gordola: Bruno Storni, [email protected] points. savings. 18 urban water systems

Copper – not a fish-friendly substance Copper is a popular material for use in roofing and facades. As roof runoff either has to infiltrate the ground or be discharged into receiving waters, copper corrosion products enter the soil or surface waters. Here, the copper is toxic to aquatic organisms. This problem was recognized largely as a result of Eawag’s efforts, and possible solutions have been identified by Eawag researchers.

At the Eawag testing facility, Michele Steiner studied the effectiveness of various granulates In this drain, roof runoff is collected from a new housing development for filter systems. The most suitable combination is now being used to treat roof runoff where copper sheeting was used for roofing. Twelve individually contaminated with copper, e. g. at the Zurich University Law Faculty library building (top right), replaceable filter cartridges filled with granulate purify the water before which was remodelled by Santiago Calatrava. it is released into a stream. urban water systems 19

Filter cartridges containing granulated ferric hydroxide and calcite are inserted at the bottom of the drain.

Patrice Goosse, an employee of the start-up based in the Zurich Technopark, reviews the measurement data. The results indicate that the efficiency of the granulate is over 98 %. Bottom: Goosse and Steiner explain the system.

From PhD student to entrepreneur As Michele Steiner says, “The simplest solution to the copper problem is obvious – avoid the large scale use of copper and zinc for roofs and facades.” At some sites, however, this is not possible, or copper is expressly specified by architects and clients. With large copper surfaces, filters are now essential to ensure compliance with quality standards for surface waters. Accordingly, Eawag sought to identify a simple method of removing copper from roof runoff. Having worked on this problem in his doctoral thesis (supervised by Professor Markus Boller), Steiner saw an opportunity to apply his expertise commercially. With his spin-off company wst21 and a partner from the construction sector, he developed the col- lection system with replaceable filter cartridges, for which a patent is pending. Like Steiner, increasing numbers of PhD students and other researchers are venturing into the marketplace. Eawag supports these initiatives as far as possible. For this purpose, it is also a member of the “glaTec” association. This technology centre established by Empa in Dübendorf in 2008 serves as a business incubator, supporting innovative start-ups in the materials and environmental technology sector. AquaticWater ecosystems as a

At Eawag, aware of the tensions between the use and protection of water resources, we carry out research on aquatic ecosystems and develop solutions for the sustainable management of water and water resources. We investigate the research effects of human interventions and climate change on the quantity and quality of water Curiosity is not enough available and provide scientific foundations for successful restoration projects. As well as species Lukas Indermaur, who studied Biology at Bern Univer- and their aquatic habitats, we focus in particular habisity, worked on his thesis at Eawag from 2004 to 2008. tat on the genetic and evolutionary basis of bio In the wild alluvial landscape of the Tagliamento river in diversity. northern Italy, he investigated the ecology of amphibians. Their terrestrial ecology in particular has been little studied to date, as on land these animals generally remain well out of sight (cf. article on p. 27). For Indermaur, it was fascinating to observe and analyse with scientific detachment. But he also invested a lot of energy in devis- ing and conducting experiments: “Just asking questions doesn’t make you a researcher,” he says. “The quality of research projects anddepends crucially re source on the operational capacity brought to bear.” Although his projects often called for round-the-clock efforts on his part, he emphasizes that success was only possible thanks to numerous helpers – and the ex- changes with other researchers around the world which are now part and parcel of scientific life. In this respect, Indermaur adds, Eawag is highly attractive for researchers “because here all types of water-related expertise are combined under one roof and cross-cutting projects are encouraged.” Teaching Tracing evolution

Ole Seehausen, Professor of Aquatic Ecology and Evo- Water aslution at Bern University, is Head of the Fisha Ecology and Evolution department at Eawag. His research interests include the question of how natural or anthropogenic changes in environ- consulting mental conditions affect the evolution and extinction of The contact point for the species. In 2008, his fishing community study of speciation driven by the diver Susanne Haertel-Borer, who holds a PhD in Biology, is sification of sense co head, together with her francophone colleague Guy organs in cichlids Périat, of the Swiss fishery advice centre FIBER, which is was published as a based at Eawag. The centre provides information on leading article in lakes and rivers, fish habi tatNature (cf. article on and fishery manage- p. 22). Although the ment for fishermen, biologist is a full-blooded researcher, he devotes more fishery officials and than half of his time to teaching and the supervision of other interested doctoral students – an onerous duty? “No,” Seehausen parties. FIBER also insists, “I enjoy it when I’m able to infect young people receives support with my enthusiasm for research. And I’m the one who from the Federal learns most in the process.” For him, teaching is the best Office for the Envi- way of better understanding what he is working on. ronment and the “Students’ questions, free of any preconceptions, force Swiss Fisheries me to re-examine my own views all the time,” he says. Association (SFV). “Without teaching, research tends to get out of touch.” Haertel-Borer travels And the converse, in his eyes, is just as disastrous: a lot, addressing fishery associations, running seminars and re source“Professors who just read from a textbook they wrote or contributing her expertise in the field. “FIBER creates 25 years ago don’t go down well with students.” opportunities for direct knowledge transfer from research to authorities and practitioners,” says Haertel-Borer. “Thanks to Eawag’s extensive network, we gain first- hand information about new developments in this country and abroad, and we can communicate this rapidly; at the same time, we are able to feed practitioners’ questions into the research sector.” And what role do members of the fishing community play? “They are key actors on surface waters,” says Haertel Borer. “Their regular presence on rivers facilitates the monitoring process, and they actively support water resources in various ways. As they are well organized and also work with young people, they are themselves often required to answer queries on water-related questions.” www.fischereiberatung.ch

Aquatic ecosystems 23

Speciesformatiandon disappearance influencedhumans by

Female cichlids from Lake Victoria whose eyes are more sensitive to blue – an adaptation to the ambient light colour in shallow waters – will choose a metallic blue mate. Those adapted to the light conditions prevailing in deeper waters, and therefore more attuned to red, will prefer a bright red male. These mating preferences can be strong enough to drive the formation of new species – provided that habitat diversity is not reduced by human activities. A similar process has been observed by Eawag researchers in a Swiss lake: adaptation to different depths in Lake Lucerne has led to the formation of several distinct whitefish species – including one not previously identified as such.

The role of natural selection in the formation of new species without geographical isolation is still much debated in evolutionary biology. The development of brightly coloured cichlid species in African lakes within only a few thousand been provided for the first time in a widely reported study, years – a brief period on the evolutionary timescale – sup- which has received much attention. ports the hypothesis that sexual selection (due to mate choice) may contribute to speciation, without populations Seeing and being seen being geographically isolated from each other. In the case In the study, evolutionary biologist Ole Seehausen (Eawag of African cichlids, it had been suggested that mating and Bern University) and his co-authors demonstrate that preferences were attributable to differences in colour female cichlids from Lake Victoria whose eyes are more perception. Compelling evidence for this theory has now sensitive to blue tend to prefer blue-coloured males, while females with photoreceptors better able to detect red light choose males with red nuptial coloration. The different visual receptor pigments were distinguished by the team on the basis of DNA and protein sequences.

With the aid of special types of nets, whitefish were caught at various specific depths in Lake Lucerne, including a newly discovered species. Biologically speaking, all species of whitefish are young, as they have evolved since the last ice age. Evolution does not always require the vast timescales observed in the case of the coelacanth (bottom), which first appeared 400 million years ago. (Photos: Baenz Lundsgaard-Hansen, Andri Bryner). 24 Aquatic ecosystems Photos: Ole Seehausen, Eawag

Nuptial coloration in males of the cichlid species Pundamilia nyererei (left) and Pundamilia pundamilia is adapted to the red or blue ambient light of their respective habitats and to the corresponding visual sensitivity of the females.

The DNA sequence of the genes underlying the visual pigments also shows that specialization did not occur by chance but was in turn due to natural selection. Colour evidently also adapted to this situation: males with a red sensitivity differs according to the water depth at which breeding dress predominate in deeper water, while blue- the fish are found. Fish living in deeper water are more coloured males are dominant in shallower water. sensitive to red, and those in shallower water are more An ancestral cichlid species has diverged into two wher- sensitive to blue. The adaptation of visual receptors to the ever ambient light changes only slowly with increasing prevailing ambient light colour confers an advantage to water depth, as is the case in areas of Lake Victoria with fish in a certain depth range. They are better able to navi- relatively clear waters. Clear water means that there is gate and, for example, will find more food than less well sufficient room for populations adapted to different light adapted fish. At the same time, the males’ coloration is conditions, and at the same time, the populations are physically separated to a certain extent, which facilitates genetic differentiation.

Reasons for the dramatic decline in diversity of species Besides demonstrating one way in which new species can be formed, the latest findings provide a mechanistic explanation for the dramatic loss of species diversity that has occurred in Lake Victoria over the past 25 years. Eutrophication of the lake due to agricultural runoff, deforestation and urbanization has substantially increased the turbidity of the water. As a result, at many sites, light conditions change rapidly within the first metres of the water column. The different ecological niches are then so narrow and so close together that the mechanism of differential genetic adaptation can no longer operate. Thus, the authors found that at sites with turbid water, rather than distinct red and blue species, only an intermediate form can occur, not specifically adapted to either of the light niches. It is very likely that merging of species, driven by environmental changes, has contributed significantly to the decline of cichlid species diversity in Lake Victoria from more than 500 to the present total of around 250 species within merely 25 cichlid generations.

Measurement of light conditions in a cichlid habitat in Lake Victoria. Aquatic ecosystems 25

New whitefish species discovered In Lake Lucerne, a new species of whitefish has been deeper waters, oxygen was depleted. As a result, the discovered by biologist Bänz Lundsgaard-Hansen and “Albeli” shifted into shallower waters, moving closer – in his colleagues from Ole Seehausen’s research group. every sense – to the “Schwebbalchen” and “Balchen”. Unofficially, it is called the “Schwebbalchen”. Previ- Whether the increase in hybridization among the three ously, four species of whitefish were known to occur in species may ultimately lead to a single hybrid species Lake Lucerne – Coregonus suidteri (“Bal- cannot yet be said. As the lake water chen”), Coregonus zugensis (“Albeli”), It is fascinating is now cleaner again and all depths Coregonus nobilis (“Edelfisch”) and the that new species are well supplied with oxygen, there so-called “Alpnacher-Felchen”. The evo- is a good chance that all three species lutionary biologists from Eawag chose can still be will survive in Lake Lucerne. Today, the name “Schwebbalchen” because the discovered here in the “Albeli” can once again spawn in species is found at a depth of 10 – 30 m Switzerland, not deeper waters. In other large Swiss – floating (=”schweben”) between the lakes, however, improvements in water habitats of the larger “Balchen”, which just in the tropics. quality probably came too late to pre- prefers a depth of 10 m, and the smaller “Albeli”, which serve the original species diversity. These findings not lives and spawns at a depth of around 40 m. Why had only help to improve our understanding of the formation this species not previously been identified as such, even and disappearance of species but also provide a basis for though it occurs in large numbers? According to Lunds- sustainable lake fishery management. gaard-Hansen, the professional fishermen may have rarely fished in these mid-depths and had presumably identified the unknown species as young and small-sized “Balchen”.

Not from another lake The “Schwebbalchen” was determined to be a distinct species on the basis of precise measurements of 14 body shape traits, as well as analyses of 14 genetic loci. Both methods indicated that, although closely related to the Lake Lucerne “Balchen” and “Albeli”, it is clearly differentiated. However, comparison with whitefish from other Swiss lakes showed fewer similarities. Thus, it is not, as was originally supposed, a species introduced to Lake Lucerne from another lake.

Increase in hybridization In response to the eutrophication of lakes, whitefish species – like the cichlids in Lake Victoria – exhibit increased hybridization, as shown by the Eawag researchers on the basis of a large, as yet unpublished data series compiled by Pascal Vonlanthen and others. From the middle of the th 20 century, Lake Lucerne received increased nutrient Top to bottom: “Balchen” (Coregonus suidteri), “Schwebbalchen” inputs from wastewater and agricultural runoff. In the and “Albeli” (Coregonus zugensis) from Lake Lucerne.

What is a species? Various concepts of a species are found in evolutionary biology. What all have in common is that populations of a species as a group of individuals not capable of of organisms are assigned to different species if they interbreeding with members of other species is a popular coexist in nature over many generations at the same site misconception. i i i without genetically merging. Numerous species hybrid- ize occasionally but remain differentiated as long as mechanisms exist that restrict gene flow. The definition Contact: Prof. Dr Ole Seehausen, [email protected] Bänz Lundsgaard-Hansen, [email protected] 26 Aquatic ecosystems

Niche differentiation – room for numerous species Different amphibian species occupy the same types of habitat, in water and on land. How- ever, as their use of these habitats differs markedly, one species does not outcompete another, allowing for a high degree of biodiversity within a small area. The key factor is the establishment and maintenance of a wide variety of structures and environmental conditions, e. g. as a result of flooding.

When two species that share a habi- density, water depth and tempera- averaged 489 in exposed gravel sedi- tat are specialized to different envi- ture. All four amphibian species ob- ments, compared with 12 in the ripar- ronmental conditions, this is known served prefer essentially the same ian forest. In addition, metamorphs as niche differentiation. Competition types of breeding waters, but their in the river bed tended to be larger with other species can be reduced selection of sites differs: for exam- than in the riparian forest. Large, by differential use of food resources, ple, both toad species are basically warm ponds in the riverbed offer or specialization to a certain range attracted to large ponds, but smaller the best conditions for larval growth. of humidity and temperature. This – ponds are used much more intense- This is presumably mainly due to the according to biological theory – is a ly by the green toad than by the com- regular scouring of sediments, which prerequisite for a high degree of bio- mon toad. Water depth preferences reduces the density of predators in diversity within a small also differ: the green toad is highly the riverbed far more effectively than By demonstrating, area. However, very likely to spawn in very shallow ponds in the more sheltered riparian for- for example, little is known about (5 –10 cm), and the Italian agile frog est. The choice of riverbed ponds the importance of the coexistence of in deeper ponds ( 5 0 c m ) . for breeding is however a risky one, organisms with com- since offspring can be wiped out by woody deposits, plex life cycles, such Risk of flooding flooding. The number of offspring the study helps as amphibians. Over a The selection of breeding sites influ- produced in riparian forest ponds is us directly in our period of four years, ences larval growth and the number lower, but consistent; this can serve therefore, an Eawag of offspring produced. Common toad as an “insurance policy”. For the amphibian conser- team investigated how larvae completed metamorphosis growth of populations in dynamic vation efforts. amphibians use their in riverbed ponds three weeks ear- floodplain habitats, it is therefore es- Silvia Zumbach, Swiss Amphibian aquatic and terrestrial lier than in riparian forest ponds. The sential that spawning waters should and Reptile Conservation Programme habitats. The study number of juveniles (metamorphs) be maintained both in the active (KARCH). was carried out on the per square metre of spawning water riverbed and in the riparian forest. unregulated Tagliamento river in the Friuli region (northeastern Italy). This wild river landscape, with riparian forests and a river corridor up to 2 km wide (depending on water levels), is among the last major pristine amphibian habitats surviving in Europe.

Shallow or deep? We studied the use of breeding waters by two toad and two frog species. At the same time, we recorded environmental factors such as prey

A complex life cycle The life cycle of semi-aquatic amphibians is among the most complex in the animal kingdom. The eggs and larvae develop in the water. The larvae hatch in 2– 3 weeks in the case of the common toad and in 3– 6 days for the green toad. Larval development until metamorphosis takes several months. Juveniles (metamorphs) and adults of most species aestivate and overwinter in secluded terrestrial habitats, where they spend most of their time. Typical spawning pond in the riverbed. Aquatic ecosystems 27

weeks, including often fruitless noc- turnal searches. Using antennas and receivers, we were then able to keep track of the toads day and night.

Popular woody deposits The two toad species were found largely in the same habitat types (see graph), with piles of woody deposits being used particularly frequently Woody deposits offer protection against Common toad (left) with a 5 g transmitter and green toad with a relative to their availability. Woody desiccation, provide a foraging ground and 2 g transmitter. promote the development of new habitat deposits clearly play a key role in the types. summer habitat. This is supported by three considerations: E According to the statistical evalu- No place to hide ation, the number and size of woody In their summer habitat, as well as deposits is a key factor determining foraging, amphibians seek protection the extent of the summer habitat for against desiccation and refuge from both toad species. predators. Little is known about how E In the exposed gravel bed – with their selection of terrestrial habitat temperatures up to 46 °C – woody patches is affected by environmental deposits are often the only structure factors – temperature, habitat type, offering pioneer species such as the density of prey and competitors, etc. green toad protection against desic- Accordingly, niche differentiation has cation and predation. not previously been demonstrated in E Woody deposits promote the de- terrestrial habitats, which also has to velopment of other habitat types ( pio do with the retiring habits of amphib- neer vegetation, islands, temporary With a tracking antenna and receiver, the ians. We wished to find out whether pools), thus contributing significantly radio-tagged amphibians could be located niche differentiation also allows two to a richly structured floodplain. day and night. co-occurring toad species to coex- Using the survey data and computer ist in their summer habitat. For this models, we also showed that while purpose, we fitted 56 common and both toad species occupy the same e. g. substantial variation in tempera- 59 green toads with mini‑transmit- habitat types, they do so for different ture, predation pressure and food ters. These were attached using reasons: woody deposits, for exam- resources. This is the key require- waist- belts and removed at the end of ple, are used by the green toad for ment for coexistence, and hence for the study. Accumulating this number thermoregulation (owing to the lower a high degree of local biodiversity. of “research subjects” took several temperatures), and by the common Large-scale river restoration projects toad for foraging. The availability of thus offer great potential for promot- woody deposits depends on an in- ing amphibians in aquatic and ter- tact riparian forest and natural flood restrial habitats. Top priority needs to 30 dynamics. be given to the re‑establishment of 25 natural flow regimes, including ripar- Common toad 20 Green toad Natural dynamics ian forest dynamics. i i i 15 Our study demonstrates niche differentiation for amphibians both in

Use index 10 the larval stage and in adults. It thus 5 explains how species with complex 0 life cycles can coexist. Surprisingly, the results concerning aquatic and Gravel Woody Pioneer deposits terrestrial habitat selection both led sediments vegetation

Islands with to the same conclusion: natural flood

Island edge with dynamics preserve open and richly woody vegetation woody vegetation structured habitats, which are suit- Contact: Use index: ratio of habitat use intensity to able for demanding pioneer species Dr Lukas Indermaur, availability of a given habitat type. The graph but also for non-specialists. Richly [email protected] is based on 2500 fixes for the green toad Prof. Dr Jukka Jokela, and more than 3000 fixes for the common structured habitats are characterized [email protected] toad. by diverse environmental conditions, 28 Aquatic ecosystems

Three-spined stickleback: successful invasion of Switzerland Until over a century ago, the three-spined stickleback in Switzerland was only found in the Basel region. It subsequently spread rapidly throughout the country, becoming remarkably diverse. Its success appears to have been due to the combination of different genetic lineages.

The three-spined stickleback, a fish populations evolving that not only of up to 10 centimetres in length differ in appearance but also occupy but of minimal economic signifi- widely varying habitats – from small cance, is found almost all over the streams to the open waters of the northern hemisphere Over the past largest lakes. The greatest diversity 15,000 years, the stickleback rap- is to be found in the region around idly diverged into a wide variety of Bern and Neuchâtel. types. Although closely related genetically, these differ markedly from Detective work based on one another in appearance, preferred genetic analysis habitat and behaviour. For example, Previous attempts to explain how Two male three-spined sticklebacks: a typical the species occurs in seawater and the three-spined stickleback invaded specimen from the Rhine at Basel (left) and in freshwater, and while the marine Switzerland after 1870 have been a hybrid from the Aare at Bern (right). type has well-developed bony lateral purely conjectural. It is considered plates, this armour was gradually lost likely that humans played a key role in in the freshwater forms. this process: the stickleback is a fairly Numerous possible combina- robust species which – unlike its nat- tions: a recipe for success Highly adaptive species ural predators – is barely affected by In the region around Lake Neuchâtel The remarkable evolutionary history river engineering structures or canali- and Bern, where the three lineages of this species can also be traced zation measures. Eawag researchers meet, the researchers found a partic- in Switzerland. When the glaciers have now used genetic methods to ularly high degree of diversity – both receded 10,000 years ago, making investigate the evolutionary history genetically and in the appearance of way for rivers, the stickleback’s ma- of the stickleback. Hundreds of spec- the fish. In these “hybrid zones”, the rine ancestors, originating from the imens were collected at 23 sites, and hereditary characteristics of three Atlantic, reached Switzerland via the their genetic fingerprints and exter- different evolutionary lines were Rhine. Until around 1870, however, nal traits were compared both with available to the offspring. Kay Lucek the Swiss stickleback population was one another and with European refer- is convinced: “That’s what drove the confined to the Basel region. Over ence populations, so as to construct rapid evolution and made it possi- the next 100 years, it spread inva- a phylogenetic tree for the Swiss ble for the stickleback to success- sively right across the country, with stickleback. fully colonize such a large number of diverse habitats within a very short Historical releases period.” It was shown that today’s stickleback In addition, the stickleback hybrid • Original type entering Switzerland via the Rhine population in Switzerland is derived zones illustrate the fact that biodi- ••• Introduced from the southern Rhône • Introduced from the Baltic catchment from not one, but three evolutionary versity can also recover after having lines. The first line is represented been temporarily decimated – in this by the population around Basel. The case, by the Ice Age. Comparison second is formed by individuals from of hybrid zones with areas where the southern Rhône system released only one lineage occurs should also in the Geneva region around 1870. further elucidate the mechanisms of The third line goes back to fish, invasive spread. i i i originally from the Baltic catchment, which were released in the Rhine near Lake Constance at about the same time. These findings accord well with historical records also re- viewed by evolutionary biologist Kay Contact: The various lineages of the three-spined stickleback. A hybrid zone Lucek – the fish released probably Kay Lucek, [email protected] has clearly arisen in the Bern Neuchâtel region. (Map © swisstopo) came from aquariums. Aquatic ecosystems 29

Hydropeaking: impacts on migrating fish

Using radio transmitters, Eawag has studied the migration of endangered lake trout in the Alpine Rhine. The fish swim more than 100 km upstream, from Lake Constance to their spawning grounds in Graubünden. But they are adversely affected by intermittent releases of water from hydropower plants.

To meet peak electricity demand, Weekend migration 6 about a third of Switzerland’s major Since a fish ladder was installed at Weekdays 5 hydropower plants operate in “hydro- the Reichenau hydropower plant Weekend peaking” mode. This involves rapid in 2000, lake resident brown trout 4 artificial fluctuations in flow rates on (an endangered species) have once 3 a watercourse. Often, what is prob- again migrated upstream from Lake (km/day) 2 lematic for aquatic ecosystems is not Constance to spawning grounds in Migration distance 1 so much the minimum or peak flows the Posterior and Anterior Rhine. 0 in themselves, as the frequent alter- This was demonstrated by an Eawag a b c d e f g h i nation between high peak and low study in which fish were implanted Migration data for 9 lake resident brown trout (a–i): at the weekend, base flow. The impacts are apparent with mini-transmitters. The longest in the absence of hydropeaking operations, the distances covered are in one in four of the country’s medi- distance covered by a lake resident substantially higher than during the week. um-sized and large rivers. brown trout migrating from Lake The most serious effects of hydro- Constance to a spawning site was peaking operations occur where land 126 km. One striking finding was of fish in their first year of life re- and water meet. In non-regulated that fish cover substantially longer vealed major differences between rivers, periodically flooded zones are distances at weekends – when the stretches of the river subject to and areas of high species density and flow regime is not affected by hy- those not subject to hydropeaking. diversity. With hydropeaking, how- dropeaking – than during the week. On undisturbed stretches, 60 trout ever, the transition zone can only be The average distance covered was were found per 100 m of shoreline, used to a limited extent as a habitat 3.7 km/day at weekends and only compared with only for aquatic or terrestrial organisms. 2.5 km/day during the week (see 2 on stretches sub- Rapid declines Macroinvertebrates and plants are also the photos on p. 32). ject to hydropeaking. in water levels repeatedly washed away, as was The researchers con- are particularly shown by the Eawag Rhône-Thur Juveniles at risk cluded that young- project (2002–2006). Eawag has Despite the effects of hydropeaking, of-the-year fish are problematic since now examined in more detail the natural reproduction of lake resident adversely affected by juvenile fish can impacts of hydropeaking on fish – brown trout at their spawning sites constant fluctuations be stranded. specifically lake trout – in the Alpine was successful. However, a subse- in flow rates. Rapid Rhine. quent investigation of the density declines in water levels are particularly problematic, as the fish (and other aquatic organisms) can then be stranded close to the banks or in dried-up pools. The adverse impacts of hydropeaking can be partly mitigated, e. g. by the use of retention basins at hydro power plants. The federal authorities are currently working on regulations to address this problem, which are to be incorporated in the Water Protection Act. Eawag researchers are serving as consultants in this process. i i i

Contact: Dr Armin Peter, [email protected] Discharge of water below a hydropower plant on the Anterior Rhine. 30 Aquatic ecosystems

Revealing the secrets of the lake floor

Topographical surveys of the bottom of Swiss lakes have never been performed in such detail before. With the aid of a sonar system involving several transmitters and receivers, three- dimensional images can be produced, which show scars and deposits of underwater landslides, excavation pits, and other lake floor structures with an accuracy in the order of centimetres.

Flavio Anselmetti, a limnogeologist, is visible over a distance of almost deposits are now visible on steep is highly enthusiastic: topographi- 6 kilometres, with slide deposits de- slopes, underwater landslides could cal surveys of the bottom of Swiss tectable at a greater depth. This land- be triggered when a future earth- lakes have never been performed in slide, which is known to have been quake occurs. such detail before. On a 15-day ex- triggered by an earthquake in 1601, cursion, a team of Eawag scientists generated a tsunami, with a wave Monitoring sediment criss‑crossed Lake Lucerne aboard 4 metres high rushing across Lake transport the research vessel Thalassa, using Lucerne. Between Vitznau and Weg- The images also make it possible special sonar equipment gis, the new maps show debris from to monitor sediment transport into The highly to scan the lake floor. an immense rockfall that plunged lakes: changes in stream flows as- accurate lake The use of several trans- into the lake from the Rigi mountain sociated with climate change will floor images mitters and receivers for some 3000 years ago. Southwest of lead to altered patterns of sediment the acoustic signal yields Vitznau, the survey reveals a terminal transport and deposition. The exca- permit analyses a large number of depth moraine, consisting of debris and vation pits visible in the Reuss delta that were values per sweep. This boulders left behind by the retreating indicate that precise bathymetric formerly not means that depths can be Reuss glacier at the end of the last images could also be used for moni- measured accurate to a ice age about 15,000 years ago. The toring gravel extraction. Archaeolo- possible. few centimetres, and the project has also led to the discovery gists hoping to uncover evidence of data is then processed to produce of previously unknown moraines, settlements from earlier periods three-dimensional images. Numer- now buried in the lake sediments: (when lake water levels were lower) ous structures can thus be visualized the subsurface was investigated by have also expressed an interest in – for example, excavation pits from reflection seismic imaging after in- the images. underwater gravel extraction in the triguing surface structures had been As yet, this new survey project with Reuss delta of the Urnersee. revealed by the new data. data from Lake Lucerne and Lake Ge- neva is only at the pilot stage. It was Insights into the past Risk management made possible in cooperation with Particularly fascinating for the re- As well as providing answers to his- the University of Geneva and with searchers are the traces of historical torical questions, however, the new technical support from the Geologi- landslides or rockfalls. Southwest images are valuable to seismologists cal Survey of Norway and from the of Weggis, for example, the 4- to and sedimentologists seeking to pre- University of Ghent (Belgium). Finan- 7‑metre high scar of a major landslide dict future events: in areas where cial support was provided by swisstopo (Federal Office of Topography), the Federal Office for the Environ- ment, and the Federal Department of Defence, Civil Protection and Sport, Weggis among other sponsors. The reasons for swisstopo’s interest are clear: the new data are far more accurate than the depth contours currently shown for lakes on official maps, which are 1 2 generally based on simple soundings taken over 50 years ago. Vitznau i i i

Depth (m) 0 40 80 120 160 200

Contact: Chrüztrichter and Vitznau basins of Lake Lucerne. (1) Scar of the major landslide of 1601 (transition from orange to Dr Flavio Anselmetti, yellow). (2) Debris from a Rigi rockfall that occurred around 1000 B.C. (3) Morainic ridge deposited about 15,000 years [email protected] ago by the Reuss glacier. Aquatic ecosystems 31

Optimizing river restoration efforts

Many Swiss watercourses are heavily engineered, and successful restoration projects require careful planning. Individual planning steps are defined in the Ecomorphology Level II method jointly developed by Eawag and the Federal Office for the Environment. The result is a plan in which measures are prioritized, indicating how the greatest possible improvements can be achieved with the resources available.

Channelization, flood protection, scribed: how natural is the river bed? wastewater discharges, hydropower Is the riparian zone sufficiently wide? operations – most watercourses in Is the longitudinal connectivity im-

Switzerland are seriously affected paired by barriers? The planning ob- Scheuber Hannes by human activities. This has been jectives are then formulated by the clearly demonstrated by the exten- project managers: for example, if a sive investigations carried out using river section lies in an extensively the Ecomorphology Level I method managed area, substantial widening of the Modular Stepwise Procedure of the riparian zone may be possible. (see Box): a quarter of all rivers and In built-up areas, it may only be pos- streams have a non-natural structure sible for the channel structure to be or are heavily impacted or culverted. improved. Below 600 m above sea level, the The importance of the river section Few streams still flow as freely as the Gornerenbach in the Kiental proportion is even higher – 50 %. In also needs to be taken into consid- valley. But a detailed knowledge of the current state, compared with addition, upstream migration of fish eration in planning. Barriers have par- the original natural state, makes it possible to define realistic goals for the restoration of degraded watercourses. is impeded by 88,000 artificial weirs ticularly detrimental effects where and falls at least 50 cm high. one watercourse joins another, as There is a huge potential for resto- they make colonization of the entire ration measures, but where is the upstream section difficult or impos- Morphology/ Biology Chemistry/ Hydrology Ecotox. need for improvements particularly sible. urgent? And where can most be Studies of this kind make it possi- achieved, using what measures? ble to determine the ecological ben- These questions are addressed by efits of restoration measures. On the Ecomorphology Level II method this basis, river engineering meas- developed at Eawag. ures are elaborated, prioritized and Hydrology Ecomorphology Temperature Macrophytes Diatoms Macroinvertebrates Fish Water chemistry Ecotoxicology shown on a map. As well as a near- Physical appearance From analysis of deficiencies natural watercourse structure, partic- Level I Regional scale survey to remedial measures ular attention needs to be paid to the Level II Catchment scale survey In contrast to Level I, the Level II provision of adequate room, without method is not designed for regional which near-natural dynamics cannot The modules used for assessing watercourses. application across a whole canton. be achieved. Instead, it is suitable for detailed assessment of selected surface water Promoting acceptance Ecomorphology Level II module can systems, i. e. watercourse sections Completion of the plan for reme- be fed into other planning – e. g. a a few kilometres long, including trib- dial measures does not mean that regional drainage plan, a flood pro- utaries. As a first step, significant excavation work can begin immedi- tection scheme or a landscape de- structures and deficiencies are de- ately. However, the results from the velopment project. The assessment method provides a clear rationale for the proposed measures and spells Joint project out the benefits for the watercourse The Modular Stepwise Procedure is a project run jointly by the Federal Office for the Envi- and for stakeholders. This supports ronment, Eawag and cantonal water protection agencies. The aim is to develop standardized objective decision - making on the part methods for investigating and assessing rivers and streams in Switzerland. Operating at of authorities and the public. i i i different levels of intensity (survey steps), the methods (modules) cover structural and hydrological, biological, chemical and ecotoxicological aspects of watercourse quality. The methods are conceived primarily as enforcement aids for cantonal authorities. The procedure was launched in 1998 with the publication of the first method – Ecomorphology Level I – and additional methods have appeared periodically since then. The draft Ecomorphology E www.modul-stufen-konzept.ch Level II method is currently being tested in the cantons, and a revised (definitive) version is Project management: to be published by the end of the year. A method for assessment of the Flow Regime at Dr Simone Langhans, [email protected] Level I has also recently been developed. Dr Christine Weber, [email protected] 32 Aquatic ecosystems

Monitoring lake trout with transmitters

With the aid of radio transmitters, Eawag monitored the migration of threatened lake trout in the Alpine Rhine. The fish migrate up to 100 kilometres or more from Lake Constance to their spawning grounds in Graubünden, negotiating artificial barriers in the process. Thanks to these studies, we now know precisely what these strong swim- mers require of their spawning areas. In addition, the tracking data showed that the fish prefer to migrate at weekends, when water levels are less affected by the operation of hydropower plants (cf. also p. 29).

A male lake trout captured in the Alpine Rhine. Along with 80 other lake trout, it was implanted with a radio transmitter so that its movements could be precisely tracked – also during the spawning period in December in the Anterior Rhine gorge.

A tiny transmitter is surgically implanted in the body cavity of the lake trout. Aquatic ecosystems 33

Lake trout at a spawning site (male in the foreground). On their upstream migration, the fish swim across man-made rapids (rock ramps) and leap barriers more than a metre high – though not always on the first attempt.

To find out more about the development of eggs and the survival of newly hatched lake trout, eggs were buried in plastic boxes in gravel with good flow conditions from December to April. Almost 90 % of the eggs survived this incubation.

Observing hidden behaviour For fish biologist Armin Peter, telemetry – the use of implanted transmitters to monitor fish – is a fascinating research method. “It reveals things that otherwise remain hidden,” he says. As the radio signals can often be picked up by the receiver over long distances, it is also possible to detect fish in inaccessible reaches of rivers or in murky waters. The researchers were surprised to find, for example, that individual lake trout swam into the Posterior Rhine but then turned around after two or three days and continued along the Anterior Rhine. Peter notes: “This means that the animals’ navigational instincts are not as infallible as we’ve always thought.“ It was also believed that all fish migrate as far as possible up to the mountain streams; telemetry has demonstrated that lake trout rarely enter tributaries and that they also spawn – presumably with little success – in canalized stretches of the Alpine Rhine that are subject to hydropeaking from hydropower plants. As well as providing evidence of animals’ behaviour, such findings also indicate what measures could be taken to improve the natural reproduction of the species concerned. The most difficult part of the telemetry process is tracking the free-swimming fish directly. A lake trout can cover up to 16 kilometres within 24 hours, and up to 9 kilometres in a single night. Armin Peter is therefore glad of the help provided by his assistants in the field – usually students or technical staff. Downstream migration is even more rapid: as long as enough water flows over the dam at Reichenau, the fish can reach Lake Constance within 1– 3 days. ChemicalsSubst and their impacts ances Eawag is an internationally recognized centre of expertise in assessment of the risks posed by water pollutants. It provides vital scientific research foundations for the definition of limits and develops cutting-edge analytical methods. The Results are never definitive ongoing exploitation of new water resources means it is necessary to study not only man- Annette Johnson, who studied Chemistry in London, made pollutants but also natural contaminants has been engaged in research at Eawag since 1991, of biological and geological origin. A recent mainly in the field of geochemistry. She is currently work- research focus is the impact of nanoparticles ing on a model which can be used to estimate the risks released into the environment as a result of of geogenic contaminants in drinking water (cf. article on human activities. p. 44). On the one hand, Johnson is a pure scientist: “It’s fascinating when, after lengthy detective work, complex in Waprocesses gradually become comprehensible or can even ter be represented by a formula,” she says. But at the same time, she remains aware that the best formulae never provide a complete explanation. In addition it requires the interaction of various disciplines, e. g. the involvement of social scientists – an approach which is particularly encouraged at Eawag. In her view, the alleged conflict between academic and practical research does not exist. However, she acknowledges the principle that the closer a question is to practice, the more complex the answer will be. This raises the temptation to pro- ceed by trial and error, rather than scientifically testing hypotheses and elucidating processes. This method, Johnson admits, cannot guarantee success either: “As a researcher, I know that my answers are never definitive, but at least it’s a partial success if others take my findings as a basis for further work.” Teaching Young people keep research alive

Bernhard Wehrli, Professor of Aquatic Chemistry at the ETH Zurich, has been a member of the Eawag Directo- rate since 2005. His research focuses on biogeochemical processes in rivers and lakes and on the sustainable management of fresh consulting Subst anceswater resources. Wehrli, who is also a member of the Attracted by credibility and Research Council of international networks the Swiss National Science Foundation, Franz Adam is Head of the Waste Management and appreciates the fact Enterprises department at the Canton Zurich Office for that the compara- Waste, Water, Energy and Air (AWEL). Originally a rural tively young envi- engineer, he completed a postgraduate course in Sani- ronmental sciences tary Engineering and Water Pollution Control at Eawag are close to practice: 25 years ago. As he recalls, this helped him to move into “It’s gratifying to the environmental be able to use topical issues to present a fundamental protection field – scientific approach.” He sees his work with students as and to establish in Wa terbridging the gap between research and practice: “Thanks numerous contacts. to my dual role at the ETH and Eawag, we can offer Since then, he has students interdisciplinary courses that wouldn’t other- frequently had wise be possible.” To illustrate his point, Wehrli mentions recourse to these the seminars run jointly with the Political Science group contacts and to on international water conflicts, and the Aquatic Systems Eawag’s expertise. practical, where students have to take an integrated For Adam, Eawag approach – from initial sampling to final reporting. Eawag is a “straightforward, benefits in turn from the young participants, some of open and expert” whom go on to write a Master’s or doctoral thesis at the partner. In his de- institute. As Wehrli says, “This has a galvanizing effect, partment, Eawag is engaged whenever knowledge is since without new blood a research institute stagnates.” required which cannot be bought in from private engineering or environmental consultants. In addition, Adam appreciates the researchers’ international networks, and he rates Eawag’s expert opinions as highly credible. For example, its risk assessment of tar deposits in Lake Zurich (see p. 46) “was a key factor leading us to revise our attitude to the remediation of this contaminated site,” he says. Current AWEL projects in which Eawag is involved include studies of nanosilver in industrial wastewater and on the long-term behaviour of treated municipal solid waste incinerator bottom ash.

Chemicals and their impacts 37

Endocrine-disrupting chemicals

Is the deterioration of semen quality in Swiss men attributable to endocrine- disrupting compounds? This was just one of the many questions addressed by the National Research Programme “NRP50 – Endocrine Disruptors: Relevance to Humans, Animals and Ecosystems”. This programme, to which Eawag made significant contributions, was completed in the summer of 2008. Our research projects focused on the contamination of lakes and rivers with endocrine disruptors, and their impacts on fish.

Wastewater contains hormonally active substances. These may be, firstly, hormones excreted by humans either naturally or after the ingestion of oral contracep- tives and, secondly, substances derived from industrial data on contamination observed in Swiss rivers and car- chemicals, which sooner or later enter the environment ried out additional measurements. Because male or mal- and natural waters. This group of substances includes, formed gonads had attracted media attention, the focus for example, nonylphenols (see p. 40), certain UV filters was on estrogenic substances. Over a period of several used in sunscreens and antioxidants in cosmetics, or months, samples collected from 19 Swiss Midland rivers brominated flame retardants. were tested for estrogenic activity using a yeast assay. The values measured, expressed as estradiol equivalents Elevated concentrations below WWTPs (EEQ), varied widely from one site to another and also The question of the fish with feminized impacts of over time, between 0.2 ng/l (the detection limit) and endocrine disruptors on fish had already been raised by 3 ng/l, with extremes in excess of 10 ng/l. From 1 ng/l, the cross-cutting Eawag project on declining fish catches production of the egg-yolk protein vitellogenin – normally (“Fischnetz”), which was completed in 2004. Under the only occurring in females – was observed in male rainbow NRP50 programme, Eawag therefore compiled existing trout. Overall, however, the EEQ concentrations tended to be relatively low. Values were found to be higher downstream than upstream of wastewater treatment plants (see chart). Estrogenic activity was lower in effluents from WWTPs with sand filters than for plants without such filters. In the “MicroPoll” project, led by the Federal Lake Thun whitefish (bottom) are more commonly affected by severe gonadal abnormalities than those in other lakes. Could this be due to munitions disposed of in the lake? This hypothesis was ruled out by Eawag studies, which included work on zebrafish (top). However, a satisfactory explanation has yet to be found. (Photos: Ruedi Keller, Anja Liedke) 38 Chemicals and their impacts Steve Baskauf, bioimages.vanderbilt.edu Baskauf, Steve Embryonic development of the zebrafish – from the egg stage (around 5 hours after fertilization) to embryos at days 1 and 2 and a newly hatched fish at day 3.

Office for the Environment, Eawag is therefore investigating how the performance of WWTPs with respect to micropollutant removal can be improved by operational adjustments or via an additional treatment step, such as One factor amongst others ozonation. www.environment-switzerland.ch/micropoll The effects of estrogenic substances on trout and their reproduction were studied in the laboratory, with the Passive sampling: an alternative to grab aid of a computer model and in the field. The above- sampling mentioned protein vitellogenin was used as an indicator, Passive samplers, which take up substances in a similar since its production is stimulated in males exposed to manner to fish, have been used as an alternative to grab female hormones. This was found to occur downstream sampling. When these devices are deployed in a river, of WWTP discharge points. At the concentrations ob- specific estrogenic substances are accumulated and sub- served, however, contrary to what was initially assumed, sequently assessed. Passive samplers are now available endocrine disruptors appear to have limited impacts on for numerous compounds, such as biocides or antibiotics fish reproduction and development and on fish popula- and other pharmaceuticals. However, their deployment tions overall. Any estrogenic effects are masked by other in natural waters can be tricky. The type of sampler used factors, such as habitat quality, other chemical pollutants, by Eawag, for example, first had to be optimized in the water temperature or microbial pathogens. Thus, both the laboratory so as to provide comparable results for all sites, model and studies carried out on the Lützelmurg (a small and in one case all the samplers deployed were washed river in Canton Thurgau) showed that, for example, rates away by flooding. Ultimately, the results showed excel- of juvenile survival during the first winter have a much lent agreement with grab samples collected in parallel. In greater influence on fish density in subsequent years than addition, individual trout were held captive in tubes close endocrine disruptors. to the sampling points in the stream and subsequently studied. Analysis of the gall bladder – where estrogens Zebrafish used as models accumulate – confirmed the values determined by passive Under the NRP50 programme, as well as conducting sampling. This means that further fish bioaccumulation limited numbers of studies with trout, Eawag used zebra- experiments can be avoided. fish to investigate endocrine disruptors. The zebrafish, a member of the carp family, is an undemanding species. Measuring only 5 – 6 cm, these fish are sexually mature after only 3– 4 months. The females lay large numbers of

20 eggs, and the transparent embryos develop outside the 16 mother’s body – making it easy to detect any morphologi- 12 cal abnormalities at a very early stage. Using this model 8 organism, it was shown that, while sexual differentiation 2 WWTPs is certainly not due to estrogen levels alone, estrogens 5 do affect the development of other organs. If a zebrafish egg is exposed to an endocrine disruptor, this influences 4 the development of the embryonic brain. If the formation 3 of estrogen receptors is suppressed by toxic substances, 3 WWTPs Above: The passive sampler (white disk) was the lateral line (a sensory organ) cannot develop properly. 2 optimized and calibrated in the laboratory. The fish is subsequently unable to orient itself and swims Left: Total estrogenic activity determined by in circles. A more detailed account of Eawag’s research 1 1 WWTP Estrogenic activity (ng/sampler per week) passive sampling over a period of three weeks on zebrafish is to be found in Eawag News 64. upstream and downstream of WWTPs. The 0 numbers on the left indicate how many WWTPs Upstream Downstream discharge effluents into the receiving waters of WWTP of WWTP before the first sampling point. Chemicals and their impacts 39

Consensus Platforms An innovative feature of National Research Programme 50 (NRP50) was the establishment of Consensus Platforms. On the basis of the latest findings, practical recommendations on endocrine disruptors were to be jointly developed by researchers and representatives of the authorities and industry. The aim was that all parties should be able to subscribe to the final documents with as few reservations as possible. Three separate platforms addressed UV filters, brominated flame retardants and wastewater/the aquatic environment. Eawag Lake Thun mystery partly solved was represented in the second and third of these groups. It was agreed that long-term Since 2000, gonadal abnormalities have been observed in monitoring and further research are required to find out more about the hazards posed by whitefish from Lake Thun. More than a third of the males endocrine disruptors. It was also acknowledged that scientific uncertainty must not be used and about a quarter of the females are affected. As well as an argument for putting off appropriate action to reduce risk. Thus, industry representa- as fusion and constrictions of testes and ovaries, there tives stated that they were prepared, for example, to seek alternatives to certain UV filters or flame retardants. For their part, the federal authorities intend to include quality criteria for have even been cases of hermaphroditism. Alongside hormonal activity in the aquatic environment in the Water Protection Ordinance. The Plat- Canton Bern and Bern University, Eawag was involved forms’ findings are available online at: www.nrp50.ch/consensus-platforms in the efforts to identify the causes of this phenomenon – unique in its extent. Studies focused not only on water quality but also on plankton and lake sediment, i. e. on everything that whitefish come into contact with in the course of their development. Although plankton and Ubiquitous flame retardants sediment samples showed estrogenic effects in various Flame retardants are an important group of chemicals cell tests in the laboratory, this was only partly confirmed studied in NRP50; some of them are believed to be in the zebrafish study. In addition, similar results were endocrine disruptors. These brominated compounds are obtained with samples from Lake Brienz, where whitefish used, for example, in computer housings, fabrics or are scarcely affected by abnormalities of this kind. So insulation materials to prevent rapid combustion. With a far – to the regret of the media, which would have gladly sediment core collected from the Greifensee, Empa and reported the mystery solved – researchers have only been Eawag researchers demonstrated how concentrations of able to discount certain theories: neither the munitions brominated flame retardants have increased rapidly since formerly dumped in the lake nor wastewater from the 1980. The problems posed by these compounds arise Lötschberg base tunnel excavation works appear to play a not only from their widespread use but also from their significant role. The project has however found evidence distribution: they are even found in isolated mountain that the sediment contains a dioxin-like substance and lakes, which means that they must also be transported compounds that disrupt the development of the immune by air. However, they also appear to be released into the system. As the source of these compounds is unknown, environment via municipal and industrial wastewater: in the detective work will continue. brown trout from river stretches that carry wastewater, concentrations of flame retardants were found to be up to five times higher than in farmed rainbow trout. As yet, there is no evidence to suggest that the concentrations observed are harmful to the fish, and certain flame retardants have now been banned in the EU. Nonetheless, the researchers insist that the search for alternatives should not be neglected since degradation products of suppos- edly unproblematic compounds may themselves prove to be endocrine disruptors. i i i

E www.nfp50.ch E Special issue of the journal Chimia (5/2008) E Eawag News 64, June 2008 Contact: Dr Marc Suter, [email protected] Tubes allowing the passage of river water were used to hold trout Dr Etienne Vermeirssen, [email protected] captive at measurement sites. 40 Chemicals and their impacts

Nonylphenols: it all depends on the mixture Nonylphenols are toxic, endocrine-disrupting contaminants, which always occur as a mixture of different isomers. Eawag has been studying these widely distributed substances for many years. New findings show that the isomers are differentially degraded by bacteria, possibly leading to an increase in the estrogenic risk posed by the mixture.

Every morning around 9 a. m., Frédé about 650,000 tonnes of nonylphe- ferent rates. In their experiments, the ric Gabriel heads for the Eawag cafe- nol polyethoxylates are manufac- Eawag researchers offered technical teria, clutching a sheaf of documents tured each year. nonylphenol to a bacterium which under his arm. Over a quiet cup of As Gabriel explains, the nonylphenol they had isolated from activated coffee, he likes to plan the day’s ex- issue provides a perfect illustration sludge from a wastewater treatment periments or read an of how toxic compounds can arise plant. The degradation products The environmental article. But today he is in the environment from relatively were then analysed by mass spec- risk of nonyl explaining to a visitor harmless anthropogenic starting trometry. After 9 days, some non- the findings of his lat- materials. At wastewater treatment ylphenol isomers were completely, phenols can be est research, carried plants, nonylphenol polyethoxylates but others only partly degraded. The seriously under out in Hans Peter Koh- undergo microbial degradation, with rate of degradation depended on the estimated if only ler’s Environmental toxic nonylphenol being released chemical structure: isomers with Biochemistry group into the environment as a result. In bulky side chains in the immediate the overall – in the Environmen- Switzerland and the EU, the use of vicinity of the phenol ring were much concentration is tal Microbiology de- nonylphenol and its ethoxylates has less readily degradable than isomers determined. partment – as part been heavily restricted by legislation with smaller side chains at this posi- of National Research for some years. In the US and most tion. Given their structure, however, Programme 50 (NRP50) on “Endo- other countries, however, no restric- as Gabriel points out, the recalcitrant crine disruptors”. Kohler and Gabriel tions are in place as yet. nonylphenols could exhibit particular- are studying nonylphenols – highly ly high levels of estrogenic activity. toxic, endocrine-disrupting environ- Nonylphenols: Microbial degradation may thus leave mental contaminants which are used a complex mixture intact precisely that part of the nonyl- in the synthesis of nonylphenol poly- On account of their structural rela- phenol mixture which poses a high ethoxylates, an important group of tionship to the female sex hormone estrogenic risk. Gabriel concludes: non-ionic surfactants. Polyethoxy- 17b‑estradiol, nonylphenols can have “This means that effective monitor- lates serve to emulsify fat in water endocrine-disrupting, estrogenic ef- ing – as required by the EU for nonyl- and are used in products such as fects on many vertebrates. So-called phenols – is only possible if individual detergents, pesticides, paints and technical nonylphenol, used in sur- isomers are measured.” And, as he plastics, but also in many industrial factant production, is known to be a gathers up his papers and clears production processes. Worldwide, complex mixture consisting of over away the coffee cups, Gabriel adds 100 isomers, which are not only that the research group is now seek- degradable to varying extents but ing to isolate the enzyme responsible also vary in their estrogenic activity. for degradation. i i i Gabriel emphasizes: “In our study, we were able to confirm the influence of the chemical structure on estrogenicity and thus also demonstrate how important it is, when assessing the environmental risk of nonylphenols, not to lump all the components together.”

Recalcitrant isomers – more potent endocrine disruptors? After being released from nonylphe- Contact: nol polyethoxylates, nonylphenol is Dr Hans Peter Kohler, [email protected] itself further degraded, but the vari- Dr Frédéric Gabriel, [email protected] Frédéric Gabriel explaining his findings. ous isomers are broken down at dif- Chemicals and their impacts 41

Silver nanoparticles: toxic to algae

Silver nanoparticles with useful antimicrobial effects are increasingly found in consumer products, but little is known about their environmental impacts. Eawag researchers have shown that these particles inhibit photosynthesis in algae. This can be explained by the known toxicity of the ionic silver present in solution as well as the metallic particles. But, strikingly, the nanoparticles are more toxic than a silver ion solution in itself.

As the production of nanomaterials pearing in the environment raises opens up new possibilities for indus- the question of whether and to what trial and commercial applications, extent they pose environmental risks. a growing number of This partly depends, Eawag/RuediKeller consumer products are The nanoparticles of course, on the exploiting the benefits are more toxic to quantities released. of synthetic nanopar- But we also need to ticles. For example, the algae than understand how the nanoparticles are used the silver ions in particles behave – in cosmetics, textiles, themselves. e. g. in surface wa- detergents and foods ters – and how they to impart dirt-resistant, water-repel- affect plants and wildlife. As yet, lit- lent, bactericidal or even ultraviolet- tle is known about these processes. absorbing properties. Eawag is therefore carrying out studies on the fate and toxicity of syn- Risk of environmental thetic silver nanoparticles. Owing to releases the well-known antimicrobial effects With the strong growth in commer- of silver, these are among the most cial applications, it is also increasingly widely used particles. likely that nanoparticles will enter the aquatic environment in the course Interactions between algae of production, use or disposal. This and nanoparticles was recently demonstrated by a Our experiments were conducted joint Eawag/Empa study of synthetic using green algae and metallic silver This set-up was used to measure the inhibitory effects of silver on al- titanium dioxide nanoparticles. These nanoparticles with an average size of gal photosynthesis. particles are used, for example, as a 25 nm (1 nanometre = a millionth of a whitening pigment in facade paints millimetre). It was rapidly shown that and are released into the environ- the particles inhibit photosynthesis in when the particles are in contact with ment as a result of weathering, i. e. in the algae. However, it was not initial- the surface of the algae – by a mech- rainwater runoff. ly clear whether this effect is in fact anism that has yet to be elucidated. The prospect of commercially pro- attributable to the nanoparticles or Secondly, we found clear evidence duced nanoparticles ultimately ap- merely to the presence of dissolved that the minute particles are taken silver (concentration around 1 %). up by algal cells despite their protec- We therefore used the amino acid tive cell walls – a significant finding,

120 cysteine, which immediately binds since the nanoparticles could have 100 free silver ions, so that they are no toxic effects inside the cells. We are 80 longer available to the algae. At once, therefore exploring this hypothesis in 60 the toxic effects were abolished. our current research. i i i 40 This result clearly assigns the 20 AgNP “blame” for toxicity to the free silver AgNO 0 3 ions. However, this is not the whole Photosynthetic yield [%] 10 – 4 10 –2 1 102 104 truth: compared with a control experi - Concentration of silver ions Ag+ [nM] ment involving silver nitrate, algae ex- Comparison of the toxicity of silver nano posed to nanoparticles show effects particles (AgNP) and a silver nitrate (AgNO3) at far lower silver ion concentrations solution, as measured by the photosynthetic than in the absence of nanoparticles yield, which declines as silver ion concen (see graph). This can be explained by trations increase. The inhibitory effects of Contact: the nanoparticles appear at far lower silver two processes: firstly, the formation Dr Renata Behra, [email protected] ion concentrations than for silver nitrate. of silver ions is evidently increased 42 Chemicals and their impacts

Reduced leaching of herbicides from bitumen sheets Environmental researchers are occasionally accused of alarmism by representatives of the private sector – but not in the case of a joint Eawag/Empa project which investigated the leaching of herbicides from bitumen sheets. Here, close cooperation with manufacturers led to significant product improvements within a short time.

Bitumen sheets – popularly known we were able to discuss our findings as roofing felt – are widely used. In and our proposals for measures to Switzerland, around 5 million m2 of reduce herbicide leaching. This led, flat roofs are constructed each year, for the first time, to collaboration be- and more than half are sealed with tween the three biggest manufactur- bitumen membranes. They are also ers, who have now optimized their used in foundations and on under- formulations and switched either to ground garages with green roofs. HE or to Preventol-B5 – a product newly developed on the basis of the Water pollution study. B2 is no longer being used. In demonstrated addition, the producers have revised Many bitumen membranes contain Root-resistant bitumen sheets are used to their recommendations for use and the herbicide mecoprop, which is seal a flat roof which is to be extensively the information included on pack- designed to prevent root penetration. vegetated. ages. They now recommend that This substance enters the environ- root-resistant sheeting should only ment after being leached out by rain- for B2. Leaching of B2 is particu- be used where it is actually needed, water, as was shown by Eawag stud- larly marked at the beginning – after i. e. on genuine green roofs. As a ies of flat roofs carried out ten years 190 days of natural weathering, con- result, the use of root-resistant bitu- ago. Pollution of surface waters with centrations were reduced by half. In men sheets was reduced to 60 % mecoprop has been demonstrated: the case of HE, mecoprop concentra- in 2008, and a reduction to 40 % in the River Glatt, for example, the tions remained in a similar – initially is expected for 2009. In the longer quality standard of 0.1 µg/l specified already much lower – order of mag- term, these two measures combined in the Water Protection Ordinance nitude. The mean amounts of herbi- could prevent 96 – 98 % of mecoprop is often substantially exceeded. In a cide released per square metre were leaching. It will now be possible to recent study, we investigated to 4 mg for HE and 80 mg for B2 under reassess the most sustainable way what extent leaching still occurs from our lab conditions. of managing runoff from roofs with currently available products, how the The rainwater runoff samples collect- enhanced bitumen sheets: by drain- s i t u a t i o n i n u r b a n r a i nw a te r r u n o f f i s to ed from the housing development at age to wastewater treatment plants, be characterized, and what measures Volketswil (Canton Zurich) showed via separated stormwater sewers to could help to reduce contamination. substantial differences in herbicide receiving waters, or through control- concentrations. Significant contribu led decentralized infiltration. i i i Extensive testing tions derived from sealing mem- Sixteen products labelled as “root-re- branes in foundations and from green sistant” were tested in the laboratory roofs of underground garages – not This study is part of the URBIC project, which is investigating the leaching of and aged under defined conditions. only from flat roofs, as had originally additives from construction materials, In addition, two gravel-covered roofs been assumed. Just before storm- and their effects on the quality of rain were exposed to artificial rainfall and water is discharged into the Chimli water runoff. URBIC measures material the roof runoff was sampled. Lastly, bach stream from the separated flows from the source to receiving wa- the occurrence of mecoprop in rain- sewer, mecoprop concentrations of ters and assesses impacts on organisms. This work is supported by the Federal water runoff was studied at several up to 10 µg/l were measured. In the Office for the Environment (FOEN) and points along a separated stormwa- stream itself, concentrations in the the Canton Zurich Office for Waste, ter sewer draining a new housing same order of magnitude were re- Water, Energy and Air (AWEL). The study development. The results are clear: corded during several rainfall events. described above is a joint Eawag/Empa among the most commonly used project. root protection agents with the trade Successful measures E www.eawag.ch/urbic names Herbitect (HE) and Preven- Throughout the study period, thanks Contact: tol-B2, leaching of mecoprop is at to extremely open cooperation with Dr Michael Burkhardt, [email protected] least 10 –20 times lower for HE than the bitumen sheet manufacturers, Chemicals and their impacts 43

Broadening and tightening the net

The Rhine catchment is a source of drinking water for more than 20 million people. So, given the need to detect and identify problematic substances as early as possible, it is little wonder that the Rhine is among the world’s most closely monitored river systems. In cooperation with the Federal Office for the Environment and the Environment and Energy Office of Canton Basel-Stadt (AUE), Eawag is investigating how the latest analytical methods can be used to detect substances in the Rhine not previously covered by monitoring programmes.

The Weil am Rhein monitoring sta- matography with high-resolution tion, lying about a kilometre below mass spectrometry. This makes it

the point where Germany, France possible to determine molecular mage Archive and Switzerland meet, aims to detect masses with an accuracy that regis- possibly toxic substances at an early ters the mass of a single electron. stage, so that waterworks can be ETH Library, I alerted and the Rhine ecosystem Promising tests protected. The substances also need The study recommended the use of to be identified so that their source this type of tandem system. Using can be determined and pollutant the test system (LTQ Orbitrap), 88 % discharges controlled. of 211 selected micropollutants were detected down to low ng/l levels with Complex measurements a single enrichment method. Screen- Unlike water levels or temperature, ing of the 12 Rhine water samples The Rhine port in Basel. After the devastating Sandoz chemical fire the measurement of potentially haz- yielded 672 positive findings, com- in 1986, the riparian states agreed to implement a joint Rhine monitor- ardous substances poses complex prising 84 different substances, in- ing programme. challenges for the Rhine monitoring cluding 40 pesticides and pesticide authorities: transformation products, 26 pharma- E Measurement must allow a large ceuticals, an anticorrosive agent and tion can be increased by predictions number of organic pollutants to be several industrial chemicals. Thanks that narrow down the expected detected, within hours if possible. to its resolving power, the system range of substances – if not mak- Traditional analytical methods – gas is in principle also capable of de- ing the needle bigger, then at least chromatography coupled with mass tecting unknown pollutants that may reducing the size of the haystack. spectrometry – cannot detect all the occur at high concentrations in the Eawag is therefore currently devel- relevant substances, and the prepara- Rhine following major accidents. In oping prediction models to facilitate tion of samples is time-consuming. combination with the technologies the identification of transformation E Concentrations down to the low already installed, the new analytical products of pesticides, biocides and nanogram (billionth of a gram) per method should make it almost im- pharmaceuticals whose concentra- litre range need to be detectable. possible for such pollutant waves to tions and effects make them relevant While this may appear to be insignifi- flow undetected towards the North to water quality. cant, even a concentration of 10 ng/l Sea. It could also be said that the At the monitoring station in Weil, the means that a kilogram of the sub- Rhine monitoring net is being both AUE is now operating a liquid chro- stance in question is flowing down- broadened and tightened. matograph coupled with a high-res- stream each day. olution mass spectrometer. Whether E Chemical analysis primarily finds Continuous improvements this system can wholly replace tra- what is being sought. However, mon- The researchers are still faced with ditional analytical methods remains itoring of the Rhine is also supposed one problem: with liquid chroma- to be seen. For the next three years, to identify unexpected or unknown tography, the mass spectrometry the process is being overseen and substances that have been released fingerprints of compounds cannot be knowledge transfer assured by an accidentally. This calls for analytical compared directly with the existing Eawag postdoc. i i i methods that can detect compounds substance databases based on stand- of interest without selecting the tar- ard gas chromatography. Unknown get substances in advance. compounds have to be determined Against this background, Eawag col- via high-accurate mass measure- laborated in 2008 with the Federal ments. This means that a compound Office for the Environment to inves- cannot be identified definitely, but tigate the potential of an analytical only with a high degree of probability. Contact: Heinz Singer, [email protected] method which combines liquid chro- The likelihood of accurate identifica- 44 Chemicals and their impacts

Arsenic: risk identification and mitigation The contamination of groundwater with arsenic poses a risk to the health of millions of people, especially in the densely populated river deltas of Southeast Asia. To date, no method has been available for identifying high-risk areas without conducting costly sampling campaigns. Now, Eawag has developed a model that allows vulnerable areas to be pinpointed using existing climate and geological data. In addition, appropriate technologies are being developed so that contaminated water can be treated by the populations affected.

Human health can be threatened by naturally occurring substances. Worldwide, more than 200 million people are exposed to excessive concentrations of arsenic or fluoride in drinking water. These substances, leached from rocks into groundwater, are known as geogenic contaminants. In many areas, the problem is recognized but, because surface waters are polluted, new wells are continually installed – often without testing the pumped water for contamination.

Making use of available data As part of the WRQ (Water Resource Quality) project, Eawag researchers Sampling at a drinking water well on Sumatra (Indonesia). According to the new modelling have now developed a method that method, around 100,000 km2 on the eastern coast of the island is considered a high-risk area allows high-risk areas to be identi- for excessive arsenic concentrations in groundwater.

fied relatively easily, without the – more than 20,000 data points for need for expensive and time‑con- arsenic and around 60,000 for flu- Arsenic suming groundwater analysis. The oride. All the data were processed Arsenic is one of the most important inorganic contami- team, coordinated by geochemist using a uniform classification sys- nants found in drinking water. This metalloid occurs as Annette Johnson, used digital maps tem. The team then prepared a mod- a natural component of underground rocks worldwide, to compile data on soil type, geol- el combining statistical analysis and with small quantities being dissolved in groundwater ogy, climate, hydrology and topog- expert knowledge to produce global as a result of weathering. The inorganic salts of arsenic raphy in a geographical information risk maps. These provide an indica- are tasteless and odourless, but highly toxic to humans. system (GIS). At the same time, data tion of those regions where ground- If ingested over long periods, even low concentrations on groundwater were collected from water with high arsenic or fluoride can cause damage to health, including disorders of liver publications and from responses pro- concentrations is to be found. In the and kidney function, and various types of cancer. vided by authorities and institutions case of arsenic, the probability of Problems arise from the fact that firstly, arsenic concentrations can vary widely at the local level and, secondly, in many areas people are completely unaware of the risk because their well water or groundwater has never been tested for arsenic. A concentration of 10 µg/l is recommended by the World Health Organization as a guideline value for arsenic in drinking water. In the deltas of the Red River and the Mekong, Eawag detected Risk arsenic concentrations exceeding 100 µg/l in one in five Very low of the samples analysed, with maximum values as high Low as 3000 µg/l. In the Irrawaddy delta (Myanmar), a study Moderate High supported by Unicef found arsenic concentrations of more than 50 µg/l at two thirds of the sampled wells. Global arsenic risk map – modelled probability of arsenic contamination in groundwater. Chemicals and their impacts 45

contamination is particularly high in not serve as a substitute for analysis the central US, Alaska, Brazil, DR of water samples. “But thanks to the Congo and in many parts of South- maps, governments, local authorities I Cambodia east Asia. or aid agencies can tell very quickly where it might be problematic to sink Focusing on Southern Asia a well.”

Across Southeast Asia, arsenic-taint- Mickey Sampson, RD ed drinking water is causing what has New high-risk areas detected been described as “mass poisoning”. on Sumatra and in Myanmar In Bangladesh alone, according to The new model is of particular inter- Unicef estimates, 2.5 million people est for regions where no groundwa- will ultimately be affected. Each ter measurement data are yet avail- year, thousands are already dying able. Accordingly, the Swiss aquatic as a result of chronic exposure to research team applied the model to arsenic – from skin, lung or blad- the Indonesian island of Sumatra, der cancer. The WRQ project team where an area covering 100,000 km2 therefore decided to refine the risk on the eastern coast was found to be mapping for this region. In particular, at high risk for arsenic contamination. the geology of young sedimentary The researchers subsequently used deposits was incorporated into the about 100 groundwater samples to model, and more than 4600 data verify the probabilities predicted by points were additionally included. the model for a region on the border A groundwater well in Cambodia, where arsenic contamination is Deltaic deposits and organic-rich between a low- and a high-risk area. widespread along the Mekong river. surface sediments were found to be Once again, the results of analyses key indicators of groundwater arsenic were found to agree well with the contamination. predictions: 94 % of the wells in the arsenic or fluoride issue systemati- low-risk area showed arsenic concen- cally – identification of the problem, Supporting governments and trations below 10 µg/l. The maps also e. g. with the aid of the new risk aid agencies indicate an increased risk of elevated maps, is only the first step. Eawag Verification of the model using avail- arsenic concentrations in groundwa- is therefore also researching and able groundwater data points from ter in the Irrawaddy delta (Myanmar) developing appropriate treatment the Bengal, Mekong and Red River and along the Chao Phraya river north methods to allow contaminants to deltas showed that the predictions of Bangkok (Thailand) – both areas be effectively removed from pumped accorded well with reality. However, where the risk had not previously groundwater. There is a need for in areas assigned a low risk by the been recognized. systems applicable at the household, model, the risk cannot be assumed to neighbourhood or community level, be zero. “There is no such thing,” as Appropriate removal which are adapted to the local situ- Annette Johnson points out. The ge- technologies ation and do not require significant ochemist adds that, ultimately, even The goal of the WRQ project is to maintenance. As well as technology a refined model, e. g. including more provide a framework enabling the and costs, attention also needs to be data from deeper rock strata, could relevant authorities to tackle the paid to sociocultural aspects. Even the best system is worthless if it is either not accepted or not properly operated by the people concerned Respecting cultural norms (see Box). i i i One option for avoiding contamination problems is to pump arsenic-free water from deep tubewells. In Bangladesh, however, it has been shown that these public wells – often centralized facilities supported by aid agencies – are underused by the public. To investigate the reasons for this, Eawag conducted a survey involving 222 households in the rural district of Sreenagar. The most important barriers were found to be social and cultural factors. Fetching water (in Bangladesh as elsewhere) is a task for women, but in many areas religious conventions prohibit women from leaving the homestead or talking to men in public places. According to the survey, E www.wrq.eawag.ch women who were prepared to take the time to walk to the central well often Contact: felt harassed. The researchers now recommend that the authorities should Dr Annette Johnson, [email protected] plan decentralized wells and take cultural norms into account, e. g. by install- Dr Stephan Hug, [email protected] ing screens. Dr Michael Berg, [email protected] 46 Chemicals and their impacts

Removing toxic sludge from a reservoir

In the winter of 2008/2009, at a total cost of CHF 8.6 million, Canton Zurich is remediating a contaminated site in Lake Zurich, at Thalwil. The source of the layer of tar, covering an area of 7000 m2, is a local gasworks, which was in operation until 1930. It was originally assumed that decontamination might do more harm than good. However, a risk assessment conducted by Eawag showed that recovery of the contaminants was not only advisable but urgently required: they were slowly but surely being released from the sediment into the water, posing a threat to the lake as a drinking water reservoir and also to aquatic organisms.

On the pontoon the sludge empties into a buffer tank and is then pumped ashore for treatment.

The entire lake bed contamination zone is enclosed by an oil boom. Work is carried out from a floating pontoon in a “clean-up box” (measuring 15  6 m), which is lowered to the bottom of the lake. Three divers working in shifts use pumps to suck up the tar deposits, which are up to a metre thick – each day around 100 m2 of lake bed is decontaminated. Chemicals and their impacts 47

In a large shed on the shore (right), the sludge – containing contaminants such as the carcinogenic benzo[a]pyrene – is sieved, chemically treated and dewatered in a filter press (above). The residue is disposed of in a high-temperature incinerator in Bremen (Germany).

A diver can work on the lake bed (water temperature 5 °C) for two hours at a time. His activities and the supply of an oxygen/ nitrogen mixture are monitored by colleagues on the pontoon (small photo above).

The benefits of an interdisciplinary approach “Eawag is the right place to carry out such complex risk assessments,” says Professor Bernhard Wehrli, referring to the expert report on whether the tar deposits should be removed from or left on the lake floor. “We had at our disposal extensive detailed studies from cantonal agencies and the private sector. To reach the necessary conclusions, it was helpful to be able to draw on expertise from a wide variety of environmental disciplines within a short space of time.” The points to be assessed were the environmental behaviour and distribution of the contaminants in the lake, and the possibility of underwater landslides or accumulation of substances via the food chain in fish. Thanks to international cooperation at Eawag, it was relatively easy to obtain information on the best available technologies for sediment remediation. Coal tar from former gasworks contains carcinogenic substances from the polycyclic aromatic hydrocarbon group. The tar deposits at Thalwil lay in shallow water near the lakeshore. Here, sludge was regularly stirred up and brought to the surface by gas bubbles, where oil films were sometimes visible to the naked eye. The main danger, however, lurked in the deeper waters, where the sediment could have slipped. A landslide of this kind could have spread the coal tar through the lake within a matter of hours. The expert report concluded that the contaminated site posed a major risk to Lake Zurich’s ecosystem and its users. In addition, Eawag recommended removal of the contaminated sediments by suction as an appropriate remediation method.

highlights 2008 49 Eawag 2008review of 2008 was declared the International Year of Sanitation by the UN, as 2.6 billion people worldwide have no access to basic sanitary facilities. One result of poor hygienic conditions is the contamination of drinking water resources. At numerous events organized for visitors, in lectures and via a travelling exhibition, Eawag explained the significance of this dire situation and showed how our aquatic research is helping to alleviate the problem. Projects such as Novaquatis, which won the Transdisciplinary Award in 2008, show that in Switzerland, too, much work remains to be done to make problems in the water sector amenable to integrated solutions. Below, we look back over some of the year’s highlights.

oped method for the analysis of drinking water, and at another, visitors Bringing science to life measured how much energy could On 26 September, Researchers’ be recovered from wastewater. A baum and Dübendorf sites provided Night attracted more than 15,000 fascinating computer simulation per- opportunities to explain Eawag’s mis- people to the shores of Lake Zurich suaded visitors that arguments are sion and the types of water-related – and onto the steamers plying be- not in themselves enough to ensure problems that we address. i i i tween Bellevue and Zürichhorn. With that research findings are success- its own booths and presentations, fully implemented in practice. Realignment of engineering Eawag played a major part in bringing Eawag was well represented not activities science to life at this event. Among only at Researchers’ Night, but also In response to personnel changes the exhibits, sediment cores and at a variety of other events – from the and the increasingly competitive maps produced using a special sonar exhibition in Horw (Canton Lucerne) nature of the environmental engi- helped to reveal the secrets of the to the World Expo in Saragossa neering field worldwide, Eawag’s lake bed. A model house was used (northern Spain). In addition, numer- engineering departments underwent by Eawag and Empa to illustrate their ous guided tours at the Kastanien- a strategic realignment. The Proc- joint research on biocides in facade ess Engineering department, led by paints and renders. At one of our Hansruedi Siegrist, is now concerned stands, we presented a newly devel- with the development and modelling of processes in the wastewater and drinking water sector. The latter will be addressed in partnership with the Top: Researchers’ Night exhibit, demonstrating how modern hollow fibre membranes can be used in wastewater recycling. Bottom: Info Day on the subject of drinking water, held in Forum Chriesbach on 12 September. 50 highlights 2008

Award winners In 2008, various Eawag papers received national or international awards, and several Eawag research- Award for his thesis on taste and ers were honoured for their work. odour compounds in drinking water. Water Resources and Drinking Water To mention just a few examples: the Eawag received an award from the department since, with the growing cross-cutting Novaquatis project on Dübendorf conservation associa- importance of wastewater recycling, urine source separation received the tion for the near-natural landscaping treatment processes can no longer Award for Transdisciplinary Research and management of its site, while be so sharply distinguished. At the – carrying a prize of CHF 75,000 – Forum Chriesbach won the Special same time, the Urban Water Man- Prize for Green Technology – part of

agement department – headed up by td-net the 2008 “Marketing+Architektur” Max Maurer since 1 September – is Award. i i i to focus on the sustainable further development of urban water sys- Cooperation intensified tems. It will elaborate new concepts With a Memorandum of Agreement, for the management of drinking Eawag has further strengthened its water and wastewater systems and well-established partnership with investigate pollutant flows in urban the UNESCO-IHE Institute for Water catchments. i i i Education in Delft (the Netherlands). Each year, as part of the Eawag Part- Standard work published nership Programme for Developing The publication of “Rivers of Europe” Presentation of the 2008 Award for Transdis- Countries (EPP), three students tak- provides, for the first time, a com- ciplinary Research to the Novaquatis project ing an MSc at the IHE are to pursue prehensive overview of the state management team. Pictured in the middle their studies at Eawag for half a year. are project managers Judit Lienert and Tove of Europe’s major rivers. Under the Larsen. Eawag will not only benefit from the editorship of three Eawag research- good reputation of the Institute in ers (Klement Tockner, Christopher from the Swiss Academies of Arts Delft: since Master’s dissertations T. Robinson and Urs Uehlinger), and Sciences (www.transdisciplinar- often develop into doctoral theses, authors from 20 countries helped to ity.ch). Michael Berg, as part of an we will have direct access to the prepare this river science reference international team, received a best best, highly motivated students – work. Modelled on the best-selling science paper award from the re- who will ultimately help to dissemi- “Rivers of North America”, the guide nowned journal “Environmental Sci- nate Eawag’s expertise around the describes the history, hydrology, ence & Technology” for a study on world. biogeochemistry and biodiversity the use of chlorine isotope analysis Cooperation between research insti- in the assessment of chlorohydrocar- tutes within the ETH Domain was bon degradation pathways. Profes- also further intensified in 2008: a sor Walter Giger and former member joint Eawag-WSL (Federal Institute of the Eawag Directorate Professor for Forest, Snow and Landscape René Schwarzenbach were named Research) Committee will now be as “legends of environmental sci- responsible for internal review of ence” by the American Chemical funding applications submitted to the Society. They thus belong to an illus Swiss National Science Foundation trious group of only 15 scientists (SNF). Representing Eawag on this of 165 European catchments. Each worldwide whose research over body are Professor Jürg Beer (Chair), chapter also addresses manage- more than 40 years has, according M ax M aurer, P rofessor H ans Joachim ment and conservation issues. The to the ACS, “significantly influenced Mosler, Christopher T. Robinson and work offers a valuable foundation today’s thinking and practices in envi- Professor Laura Sigg. i i i for implementation of the EU Wa- ronmental chemistry”. Andreas Peter ter Framework Directive. It presents won the Otto Jaag Water Protection Multi-channel knowledge striking evidence of the severe pres- transfer sures affecting European rivers and As well as having staff teaching at the freshwater fauna. Elsevier, 728 pp., ETH Zurich and the EPF Lausanne, December 2008. i i i and at other universities and universities of applied sciences, Eawag uses other channels to ensure that our expertise and the results of our re- highlights 2008 51

Feel-good events With copious attention to detail, creativity and musicality, the three search are disseminated as widely as departments responsible for organiz- possible. In 2008, 1115 newspaper ing the 2008 Eawag Christmas party articles and radio or television reports – Sandec, Cirus and Siam – once dealt with Eawag research topics. again gave the occasion a distinctive of “Wasserkreislauf” (water cycle), Much of this coverage is due to the character, making it an unforgettable an installation in which fountains fact that media professionals trust shoot from one toilet bowl to another. Eawag to provide expert answers to The “Atmen” (breathing) installation water-related queries; in other cases, (photo) was conceived after Qiu had it was actively encouraged by our studied the development of various media releases and events or the aquatic microorganisms under the publication of Eawag News, the An- microscope. Both sides benefit from nual Report and articles in journals. this unorthodox collaboration. River Four practice-oriented Eawag (PEAK) specialist Christopher T. Robinson courses were held, on subjects rang- says: “Thanks to Ping Qiu’s ques- ing from ecotoxicology to an applied At the 2008 Christmas party, Bavaria was tions, we researchers now under- course on heating and cooling with one of the stopping points on the “Eawaga- stand much better how others see dougou” round-the-world trip. wastewater. Two well-attended our work, so we learned something events were the Info Day (12 Sep- event for the 350 guests. The team new too.” Qiu is already planning staged an ingenious round-the-world a project that takes the reverse ap- quest (“Eawagadougou”) to find the proach: scientists are to spend some best doctoral students for Eawag. time among artists in a studio and Other events such as the “Anstalts express their ideas or questions in an weihnacht” and International Food artistic form. www.artistsinlabs.ch Event in Kastanienbaum, or the PhD students’ party, certainly contributed Eawag on the road to the positive working atmosphere On 27 May, the Eawag excursion and esprit de corps at Eawag. These to Biel, Erlach and St Peter’s Island tember) on drinking water and the are also promoted, in a different way focused on the historical Jura Waters conference on the remediation of but no less effectively, by a range Correction and the current debate sites contaminated with chlorinated of popular sporting activities – from concerning regulation of the three solvents (14 May). i i i yoga to volleyball. i i i lakes. The officials responsible assured the sceptical researchers that New staff representatives Artist’s-eye view of research the major floods of August 2007 on elected During a nine-month residency spon- Lake Biel and along the Aar could In October, Eawag employees sored by the Swiss Artists In Labs hardly have been prevented even by elected new representatives for the Program, Swiss-Chinese artist Ping lake regulation measures. The rainfall period 2009–2012: administrative Qiu explored research questions volumes during that wet summer staff are to be represented by Karin and methods through dialogue with were simply too great. Of particular Ghilardi; technical staff, including ap- interest for the aquatic ecologists prentices, by Jacqueline Traber and were the video images of the fish Alois Zwyssig; scientific staff by Tom ladder at the Biel/Nidau weir. Live Gonser; and doctoral students by transmission of these images to the Simon-Lukas Rinderknecht. The out- boardroom at Bernese Power Plants going representatives are Hans Peter Ltd (BKW) had to be stopped: instead Kohler (Chair), Claudia Bänninger- of discussing kilowatt-hours and rev- Werfeli, Philippe Bradac, Christian enues, the directors were fascinated Dinkel and Brigitte Pfister. i i i by the upstream progress of the chub scientists at Eawag. She produced and other species. i i i imaginative, sometimes surprising responses to water and pressing water issues. For example, sustainable water management serves as the theme 52 highlights 2008

larly appeals to her. She intends to test and further develop products of ecotoxicology research, such as sen- Martin Ackermann: Having held sitive tests and measurement meth- the SNF-sponsored chair of Micro- Personnel ods for the assessment of chemicals bial Evolution at the ETH Zurich from or the monitoring of water quality. 2006, Dr Martin Ackermann (38) New appointments Almut Gerhardt is convinced that the was appointed by the ETH Board as Kristin Schirmer: On 1 January embedding of the centre in the ETH Associate Professor of Molecular 2008, biology professor Kristin Schir Domain represents a major oppor- Microbial Ecology in July 2008. He mer (41) became head of the Envi tunity. By being right at the heart of conducts his research in the Envi- ronmental Toxicology department. research, can help to develop practi- ronmental Microbiology department She had spent the previous four cal products on the basis of new at Eawag. His group works on fun- years as head of the Cell Toxicology findings. As she points out, the inde- damental questions about the biol- department at the Helmholtz Centre pendent centre has greater freedom ogy of bacteria, combining methods for Environmental Research (UFZ) in than private companies because its from molecular microbiology with Leipzig. She is especially interested work does not have to be exclusively evolutionary biology and ecology. in cellular processes triggered by market-oriented – a fact that will cer- He is particularly interested in the toxic substances. She says: “Only if tainly enhance the centre’s credibility division of labour in simple microbial we understand what happens in cells in the eyes of the authorities and the communities, and in bacterial stress on the protein and DNA level, can we public. responses. estimate the whole-organism effects of environmental contaminants.” The Sam Arey: Jeremy Samuel Arey (34) Retirements combination of cell biology and envi- has an MS in environmental engi- In view of the changeover from a ronmental toxicology also allows her neering and a PhD in Environmental defined-benefit to a defined-contri- to investigate the effects of chronic Chemistry from Massachusetts Insti- bution scheme at Publica (the Swiss exposure to low concentrations of tute of Technology. He first came to Federal Pension Fund), a number toxic substances or pollutant cock- the EPF Lausanne as a postdoc from of long-standing Eawag employees tails. Kristin Schirmer attaches par- MIT, and in July he was appointed retired (or took early retirement) in ticular importance to teaching stu- by the ETH Board as tenure-track 2008, including Ueli Bundi, who dents and to the practical relevance Assistant Professor of environmental served as Director from 2004 to of research: with her team, she has chemical processes in EPFL’s School 2006 (p. 54). The other retirees, patented a sampling method which of Architecture, Civil and Environ- apart from those mentioned below, permits time-integrated monitoring mental Engineering. He is head of are Erwin Grieder (Surface Waters), of biological and chemical param- the Environmental Chemistry Mod- Heidi Gruber (Staff of Directorate), eters. In March 2008, her husband, eling Laboratory (LMCE), which is Therese Haenni (HR), Beatrice Hürli- Mario Schirmer, also joined Eawag jointly supported by the Environmen- mann (Technical Services/TS), Arthur to lead a research group in the Water tal Chemistry department at Eawag Scheiber (TS), Andreas Steffen (TS), Resources & Drinking Water depart- and the Environmental Sciences and Jutta Studer (Library), Christa Surber ment. Technology Institute at the EPFL. The (Library). mission of the LMCE is to explain and Almut Gerhardt: Having come to predict the behaviour of xenobiotic Markus Boller: After working as an Eawag in June 2008, biologist Dr Al- organic compounds in the environ- assistant at the ETH Rural Engineer- mut Gerhardt has been head of the ment, together with their ecological ing Institute for two years, Markus Swiss C entre for A pplied Ecotoxicolo - and health effects. This represents Boller trained as a sanitary engineer gy Eawag-EPFL (p. 4) since it opened a strengthening of the cooperation at the IHE in Delft and joined Eawag on 30 October. As well as pursu- between Eawag and the EPFL. in this capacity in 1973. Having com- ing an academic career in aquatic pleted his doctoral thesis on contact ecotoxicology, she has managed her filtration, he became head of the own consulting and research com- Process Engineering group. For many pany, LimCo International. She says years, he was particularly interested that the pioneering dimension of in advanced phosphorus removal, developing the new centre particu- and he became the leading European highlights 2008 53

Peter Bossard: Having written his dissertation at Kastanienbaum in 1972, Peter Bossard earned his doctorate with a thesis on the methane expert in this area. His studies on and oxygen balance in Lake Lungern physicochemical wastewater treat- and joined the Eawag Limnology ment were followed by projects department in 1979. From 1989 to concerning nitrification using a wide 2001, he served as Managing Editor variety of biofilm reactors. There fol- of the journal Aquatic Sciences, and lowed, as he put it, “the drinking in 1994/95 he was ad interim head he is not only well known among water and the rainwater years and of the Limnology department. In his students: together with Heinz Bach- finally, over the last seven years, research, Bossard was mainly con- mann, he produced micrographs and everything combined in a NoMix cerned with algae as primary produc- electron micrographs of algae and [urine source separation] mixture.” ers. He studied primary production invertebrates which have appeared In the drinking water field, Markus in Lake Lucerne for over 20 years. in countless reports and books. Bür- Boller’s interests included the use of For a time, he contributed articles gi successfully championed stand- activated carbon for water treatment, to the Science & Technology sec- ardized sampling methods and was and he recognized at an early stage tion of the NZZ, which enhanced his responsible for the introduction of the opportunities of membrane tech- reputation as a communicator. In the standard zooplankton nets. As he nology, which he subsequently also mid-1970s, he was among the found- points out, “The most sophisticat- applied for the treatment of urine. in ers of “project‑oriented studies” at ed analysis is no use if inappropriate addition, he worked on the treatment the ETH – at the time, a revolutionary equipment was used for sampling.” of karstic spring water and initiated development which initially encoun- the Wave21 project (“Drinking water tered resistance from some estab- Oskar Wanner: Eawag’s interdis- in the 21st century). lished professors, but which can be ciplinary approach to research was His research on rainwater focused seen in retrospect as having paved ideal for Oskar Wanner. A mechanical not only on treatment methods (e. g. the way for case studies and other engineer (ETH), he also studied Biol- for road or roof runoff) but also on “at new approaches to the study of natu- ogy and wrote his doctoral thesis on source” measures, and for this pur- ral sciences. the hormone oxytocin at the Institute pose, he often sought the coopera- of Molecular Biology and Biophysics. tion of manufacturers, professional Hans Rudolf Bürgi: After studying In 1979, he joined Eawag’s Informa- associations and authorities. Markus Natural Sciences at the ETH Zurich tion Technology department – not Boller and his groups certainly made and writing a dissertation on lim- to be confused with today’s IT sup- significant contributions to the suc- nology under Professor Otto Jaag, port unit. He was involved in many cess of the Swiss urban water man- Hansruedi Bürgi came to Eawag in projects where systems analysis agement sector – and to Eawag’s 1968 to work on his doctorate. As he issues and mathematical problems reputation. In addition, he was always was an excellent draughtsman, he needed to be addressed. He took a strongly committed to teaching and was first called upon by Eawag Direc- particular interest in the modelling of was awarded the title of Professor tor Jaag to redesign a reference work biofilms, a research topic to which he in 1996. He was head of the En- on saprobic organisms, contributing kept returning for more than 25 years. gineering department from 1994 to more than 100 pen-and-ink draw- In recent years, as a member of the 2000, and head of the Urban Water ings. During his 40 years at Eawag, Engineering department, he was Management department thereafter. he was particularly interested in vari- concerned with the recovery of As Eawag’s “Samichlaus” (Santa ous aspects of plankton interactions. heat from wastewater (p. 15). Here, Claus), he is regarded as the father Key projects included an assessment biofilms cropped up once again – as a of the traditional Christmas party, of plankton on behalf of the Interna- common source of problems on heat and his rhymed speeches marking tional Commission for the Protection exchangers. i i i the end of the year or colleagues’ of Lake Constance (IGKB) and the departures are now legendary. development of littoral and biological interaction modules for the MODEC (Models in Ecology) project. Bürgi was also very active as a lecturer: at the ETH, he took on up to 11 teaching assignments per year. However, 54 highlights 2008

Ueli Bundi: a bridge-builder committed to sustainable water management The end of May 2008 saw the “retirement” of Ueli Bundi. No one else at Eawag has dedicated himself for so long or so persistently to Switzerland’s surface waters. Ueli Bundi championed the idea that problems should be approached holistically and solutions sought through dialogue with stakeholders – always showing a high level of personal commitment. With his wide-ranging knowledge and bridge-building skills, he was instrumental in defining Eawag’s under standing of its role and building its credibility. by Professor Bernhard Wehrli, Member of the Directorate

When Ueli Bundi first came to Eawag Biedermann, a long‑time companion in 1972 as a research associate, and former Cantonal Chemist for Ap- he applied what was then the new penzell AR, Appenzell IR, Glarus and approach of life-cycle analysis to Schaffhausen, says, “For us, Ueli highlight the possibilities of recycling was a wonderful person to deal with, and integrated resource manage- as he could see the big picture and ment. However, he soon turned didn’t get bogged down in details like his attention to water management many other researchers.” measures. Influential figure “Gewässerschutz 2000”: As well as shaping Eawag’s public a milestone image, Ueli Bundi was in charge of The “Gewässerschutz 2000” proj internal planning processes for many ect, which he led and energetically years and played a key role in the pursued, was among the pioneering development of Eawag during the environmental efforts, paving the directorships of Werner Stumm and way for Swiss water pollution con- Alexander Zehnder. From 1990, he trol legislation. His early study on was a Member of the Directorate. phosphorus pollution in the Greifen- These years included the planning see demonstrated the need for a ban phase for Eawag’s new headquar- on phosphates in detergents, which ters – Forum Chriesbach. It is largely was progressively implemented in thanks to his efforts that the ideas the 1980s. He was on the sustainability of this building It’s impossible to a driving force in the were so consistently pursued and overestimate Ueli’s elaboration of scien- put into practice. contribution to tifically based quality From 2004 to 2006, Ueli Bundi standards for water- served as Director on an ad interim integrated water bodies and methods basis. In this capacity, he led Eawag protection in for the assessment of actively, together with his colleagues Switzerland. rivers and streams. In in the Directorate, and did not shy connection with the away from strategic decisions. In Roland Schertenleib, a Member of the Directorate from 1999 to 2006, debate on ecological spite of his heavy workload, he was who shared 30 years at Eawag flow requirements, he always ready to listen to staff con- with Ueli Bundi. was the first to empha- cerns, to consult internal specialists size the crucial importance of flow and to express his appreciation for dynamics. Although these concepts lines were developed for a compre- people’s work. were initially controversial, they are hensive nitrogen policy in the agri- Ueli Bundi will continue to serve now widely accepted. culture, transport/combustion and Eawag after his retirement. In partic- wastewater sectors. His ability to ular, he is representing the institute Integrated approach bring together experts from various in the Water Agenda 21 network, In the 1990s, Ueli Bundi initiated and disciplines to explore possible solu- which he helped to initiate – another led, together with colleagues from tions was one of his great strengths. platform for the promotion of an inte- other institutions, a transdisciplinary His broad knowledge and unmistak- grated Swiss water policy. i i i project concerning the national nitro- able personal commitment to natural gen balance, in which – for the first waters earned him wide recognition time anywhere in the world – guide- and numerous friendships. As Roger highlights 2008 55

Equal opportunity and gender equity

In April 2008, the Equal Opportunity The measures accorded top priority Workgroup for Equal Opportunities. Officer at Eawag was replaced by by the EOC are improving career ad- The joint project “Fix the leaky pipe- a standing Committee on Gender vancement, strengthening the work/ line” was coordinated by Gabriella Equity and Equal Opportunity (EOC). life balance and providing mentoring Meier Bürgisser, who represented The goal of this committee remains for women, especially for postdocs. the Eawag EOC until October 2008. the same: women and men are to The last point is important because, have equal opportunities at Eawag, while almost equal numbers of wom- Reflecting on successes with balanced representation in all en and men complete doctorates, The goals, achievements and minutes areas. This requires in particular the (too) many women abandon research of the EOC can be viewed by all staff advancement of women in positions careers after a stint as a postdoc. on the intranet. This creates transpar- of responsibility within research and New guidelines for hiring should also ency and should encourage further in managerial functions. The fact that help to ensure that the number of fe- action. After all, several issues have a number of people from different male research staff reflects the pro- already been resolved at Eawag in an departments are now concerned portion of female PhD students. exemplary fashion – e. g. the estab- with gender equity creates an op- Thanks to a permanent representa- lishment of the on-site Eawag-Empa portunity to raise awareness of these tive, the Eawag EOC maintains close Childcare Centre in 2006. i i i issues. contacts with the ETH Domain’s by Natalija Miladinovic, EOC coordinator

Natural laboratory on our doorstep

E awag uses its sur roundings to show - tory on Eawag’s doorstep. This is case near-natural principles and new planned as part of the project to re- types of urban landscaping. In these store the Chriesbach stream – in co- projects, the institute’s own research operation with Canton Zurich, Fluss- findings are taken into consideration bau AG, asp-Landschaftsarchitekten and exemplified as far as possible. and other partners – which will be Measures of this kind are initiated presented for public inspection in the and coordinated by the Eco-Team. In summer of 2009. Initial construction December 2008, for example, staff work on the stream is scheduled for A Banded Demoiselle – one of Heinrich helped to establish a new pond, as early 2010. Work will begin where Bührers beautiful photos taken in the near- an existing pond had to be removed the stream joins the Glatt and will natural surroundings of Eawag. during renovation work on the labo- include a new footpath/cycleway ratory building. The new pond is the running along the Chriesbach to the sought to finance further expansion first step towards a natural labora- Eawag/Empa site. The project will of the natural laboratory, e. g. the in- be accompanied by scientific stud- stallation of an aquarium. ies. A programme for the monitoring The rich diversity offered by near- of aquatic ecology and groundwater natural surroundings is demonstrated has already been launched. by photos taken by Heinrich Bührer, a former employee. A long-time mem- Access for the public ber of the Eco-Team, Bührer docu- From 2011, an “Arena” with seat- mented urban nature around Eawag ing steps is to be established in the in all four seasons, and then archived natural laboratory area, which will be and annotated his pictures in an accessible to the general public and extensive database. In the autumn also used for teaching school classes of 2008, the Eco-Team displayed a and students. By then, another pond selection of these images in an exhi- is to be created closer to the stream, bition at Eawag. i i i which will be flooded during high- Thomas Lichtensteiger, water conditions. Eawag is contrib- Environmental Officer at Eawag uting to the funding of this project. The costs for the restoration of the Key data for Eawag (consumption of materials and energy) and details of Eco- The new pond in April 2009. In the back- Chriesbach are being borne by Can- Team projects: www.umwelt.eawag.ch ground: renovation of the laboratory building. ton Zurich. Sponsors are still being 56 ORganization chart / advisory board

Organization

Directorate Janet Hering (Director) Rik Eggen (Deputy Director) Willi Gujer Peter Reichert Bernhard Wehrli

Ecotox Centre Eawag/EPFL Staff of the Directorate Almut Gerhardt Further education, knowledge transfer, communication Peter Häni

Research departments Support Surface Waters Water Resources and Drinking Water IT Services Research and Management Rolf Kipfer Gabriel Piepke Alfred Wüest HR and Finances Aquatic Ecology Process Engineering Gabriele Mayer Jukka Jokela Hansruedi Siegrist

Apprenticeship Research topic: Max Reutlinger Aquatic ecosystems Fish Ecology + Evolution Urban Water Management Ole Seehausen Markus Boller (until 31.5.2008) Research topic: Technical Services

Urban water systems Max Maurer (from 1.9.2008) Max Mauz Water and Sanitation in Environmental Chemistry Developing Countries (Sandec) Gender Activities Juliane Hollender Chris Zurbrügg Gabriella Meier (until 30.11.2008) Natalija Miladinovic

Environmental Microbiology Systems Analysis, Integrated Eawag / Empa Thomas Egli Assessment and Modelling Peter Reichert Library Bas den Brok Research topic: Environmental Toxicology Comprehensive Innovation Research Kristin Schirmer in Utility Sectors (Cirus) Nursery Chemicals and their impacts Bernhard Truffer Joerg Klausen

Advisory Board

André Bachmann Ursula Brunner Erika Forster Günter Fritz Peter Arbenz Jürg Meyer Willy Geiger (President) Lawyer, Ettler State Councillor, Head of Environment, President Helvetas Director Waste- Vice Director, Executive Director, Brunner Suter St. Gallen Health and Safety, water Treatment Federal Office for the BMG Engineering Bächtold, Zurich Ciba Specialty Association Lucerne Environment (FOEN), Inc, Schlieren Chemicals, Basel region Bern departments 57

Directorate

Janet Hering Rik Eggen Willi Gujer Peter Reichert Bernhard Wehrli Director Deputy Director

Staff of the Directorate Ecotoxicology Centre

Peter Häni Herbert Güttinger Isabel Wiedmer Sandra Ziegler Handschin Almut Gerhardt Leader Further education Knowledge transfer Communication Leader

Research departments

Alfred Wüest Jukka Jokela Ole Seehausen Juliane Hollender Thomas Egli Kristin Schirmer

Rolf Kipfer Hansruedi Siegrist Max Maurer Chris Zurbrügg Peter Reichert Bernhard Truffer

Support

Gabriel Piepke Gabriele Mayer Max Reutlinger Max Mauz Natalija Miladinovic Bas den Brok Joerg Klausen 58 Figures 2008

Finances

Financial statement (in CHF) 2006 2007 2008 Personnel 35 203 743 37 868 533 39 498 230 Materials 2 911 752 3 260 866 3 693 473 Other general expenses 5 556 131 6 781 444 6 582 893 Infrastructural expenses 5 160 395 6 710 435 6 466 633 Depreciation 871 718 1 082 462 1 315 815 Provisions 10 088 456 296 041 8 169 630 Expenditure 59 792 195 55 999 781 65 726 674 Federal government funding 49 795 822 1 38 491 577 54 429 850 Third-party resources 13 481 019 11 564 156 13 626 998 Miscellaneous revenue 1 010 742 1 655 624 935 584 Income 64 287 583 51 711 357 68 992 432 Result 4 495 388 –4 288 424 3 265 758

1 Not including funding for building

Investments (in CHF) 9 370 632 15 823 645 3 849 680 Real estate 6 883 301 13 890 051 1 484 507 Movables 2 439 510 1 663 563 2 047 665 IT 47 821 270 031 317 508

Breakdown of expenditure 2008 Development 2002–2008 Provisions 70 Depreciation Personnel expenditure Infrastructural 60 expenses

50 Other general expenses

40 Material expenses

Third-party resources 2008 CHF million Other funding CHF 0.96 million Research funding 20 European research CHF 3.64 million programmes CHF 1.52 million 10

0 2002 2003 2004 2005 2006 2007 2008 Business-oriented research Federal CHF 3.87 million research contracts Third-party funds CHF 3.62 million Federal funding Total expenditure figures 2008 59

People

Personnel People Whereof Whereof Full-time women non-Swiss equivalents Full professors 1 7 1 4 6 Titular professors 13 2 5 13 Scientific staff (academic staff) 146 55 81 129 PhD students 72 36 40 71 Technical staff 80 39 12 68 Administrative staff 68 57 13 45 Apprentices 26 14 1 26 Total 412 204 156 358 Affiliated staff (nursery) 17 17 2 14 Trainees 2 35 13 25 35

1 Not or not directly employed by Eawag (incl. 1 Assistant Professor Eawag/EPFL) 2 Variable employment periods

Age structure Women Men Total Women Men

60–65 7 11 18 39%

50–59 29 39 68 43%

40–49 47 39 86 55%

30–39 47 65 112 42%

20–29 60 35 95 63%

15–19 14 13 27 52%

Total 204 202 406 80 60 40 20 0 20 40 60 80 Number

Percentage employment Women Men Total Origin Women Men Total 1–49 % 16 11 27 Switzerland 131 122 253 50–79 % 52 8 60 EU 53 66 119 80–99 % 31 19 50 Other 20 14 34 100 % 105 164 269 60 Figures 2008

Activities

2006 2007 2008 Supervised dissertations 107 108 119 Supervised diploma theses 104 108 97 Publications in refereed journals 194 202 253 Publications in non-refereed journals 49 55 55 Spin-offs 1 – 1 Patents, licence agreements – 1 – Service contracts 38 28 31 Prizes 24 19 12 Teaching programmes at ETHZ, EPFL 93 75 81 Teaching programmes at other universities 37 39 52 Teaching programmes at universities of applied sciences 10 4 2 PEAK courses (further education) 6 5 4 Conferences 45 54 39 Committee memberships 201 216 178

Further details and annual reports in pdf format are available at: www.eawag.ch/annualreport. Eawag, the Swiss Federal Institute of Aquatic Science and Technology, is part This Annual Report presents only a small selection of Eawag’s of the ETH Domain. This comprises the Swiss Federal Institutes of Technology research, teaching and consulting activities. It is also available in Zurich (ETHZ) and Lausanne (EPFL), Eawag and three other independent, in German. A database listing all publications by Eawag application- oriented research institutes – the Paul Scherrer Institute (PSI), the staff (including article summaries) is available online at: Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) and http://library.eawag-empa.ch/eawag_publications.html the Materials Science and Technology Research Institution (Empa). Open access publications can be downloaded free of charge. Nationally rooted and internationally networked, Eawag is concerned with The database is searchable by author, title or keyword. If you concepts and technologies for the sustainable management of water have any queries, please contact: [email protected] resources and aquatic ecosystems. In cooperation with universities, other research centres, public authorities, the private sector and NGOs, Eawag The e-mail addresses of all staff are available via the search strives to harmonize ecological, economic and social interests in water, function on the website: www.eawag.ch providing a link between science and practical applications. About 400 staff are employed in research, teaching and consulting at the Dübendorf (Zurich) and Kastanienbaum (Lucerne) sites.

Publication details

Eawag Annual Report 2008 Annual Report Eawag: Swiss Federal Institute of Aquatic Science and Technology and Science Aquatic of Institute Federal Swiss Eawag: 2008